please help me with this system of equations problem before I go insane the preferable solving methods would be through substitution or elimination
Answer:
x=8, y=0, z=-3
Step-by-step explanation:
Preferable is substitution because there is less room for mistakes but its long so here goes bare with me on this one :D
Name your equations
4x+2y-5z=47 (first eq)
x-2y+6z=-10 (second eq)
9x-7y-z=75 (third eq)
Lets take the easiest eq to isolate one variable lets take 2nd eq
[tex]x-2y+6z=-10\\x=2y-6z-10[/tex]
now this becomes our fourth eq
now again take the easiest eq to isolate another variable lets take the 3rd eq
[tex]9x-7y-z=75\\9x-7y-75=z[/tex]
now this becomes our fifth eq
and now plug in our fifth eq in the fourth eq because we now have z in terms of x and y
[tex]x=2y-6z-10\\x=2y-6(9x-7y-75)-10\\x=2y-54x+42y+450-10\\x+54x=2y+42y+450-10\\55x=44y+440\\\\x=\frac{44y+440}{55}[/tex]
and now we got our sixth equation which is x only in terms of y.
now we plug in our sixth equation in our fifth eq to get z in terms of y only
[tex]z=9x-7y-75\\\\z=9(\frac{44y+440}{55}) -7y-75\\z=\frac{396y+3960}{55} -7y-75\\z=\frac{396y+3960-385y-4125}{55} \\z=\frac{11y-165}{55}[/tex]
now we have our seventh eq and x &z in terms of just one variable y , now we put equation of z and x which is our sixth eq and seventh eq in our first eq.
[tex]4x+2y-5z=47\\\\4(\frac{44y+440}{55})+2y-5(\frac{11y-165}{55}) =47\\\\\frac{176y+1760}{55} +2y-47=\frac{11y-165}{11} \\\\\frac{176y+1760}{55} -\frac{11y-165}{11} -47=-2y\\\\\frac{176y+1760}{55}-(y-15) -47=-2y\\\\\frac{176y+1760}{55} -y-32=-2y\\\\\\frac{176y+1760}{55}=-2y+y+32 \\\\176y+1760=55(-y+32)\\176y+1760=-55y+1760\\176y-55y=1760-1760\\121y=0\\y=0[/tex]
and now finally we got y=0 now we need the value of x and z, put the value of y=0 in our seventh eq (z equation)
[tex]z=\frac{11y-165}{55} \\\\z=\frac{11(0)-165}{55} \\\\z=\frac{-165}{55}\\\\z=-3[/tex]
and now we put the value of y=0 in our sixth eq (x equation)
[tex]x=\frac{44y+440}{55} \\\\x=\frac{44(0)+440}{55} \\\\x=\frac{440}{55} \\\\x=8[/tex]
and now we got all the three values and hence the solution of the system of equation is
x=8, y=0, z=-3
the product of a number and 13 increased by 5 is -12
Answer:
13x + 5= -12
hope this helps :)
is 9/36 greater than 8/1
Answer:
No it's not
Step-by-step explanation:
The reason is because 8/1 becomes a whole number unlike the other.
Jose had the following division problem for homework. What is the quotient?
$0.56
$5.60
$56.00
$560.00
Answer: it’s C
Step-by-step explanation: I took the test :)
Answer:
C
Step-by-step explanation:
mark the other guy
:)
A bus arrives at Stop A every 14 minutes and a bus arrives at Stop Bevery 20
minutes. Both buses just arrived at their stops. After how many minutes will both
buses stop at the same time again?
A. 70 minutes
B. 60 minutes
C. 140 minutes
D. 280 minutes
*please help, I’ll give you brainliest :)
Answer:
b or a
Step-by-step explanation:
If bus A arrives after 14 minutes and bus B arrives after 20 minutes, then both buses will arrive at 140 minutes.
Given:
Bus A = 14 minutesBus B = 20 minutesHow to find the Least common multiple(LCM)Find the least common multiple of 14 minutes and 20 minutes
14 minutes = 14, 28, 42, 56, 70, 84, 98, 112, 126, 140, 154, 168, 182, 196, 210, 224, 238, 252, 266, 280....
20 minutes = 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220.....
Therefore, the least common multiple of 14 minutes and 20 minutes is 140 minutes.
Learn more about LCM:
https://brainly.com/question/10749076
If a number has no pulse or minus sign, does that mean it’s usually a positive or negative number?
Answer:
positive
Step-by-step explanation:
Answer:
It means it is usually positive
Step-by-step explanation:
The positive sign is invisible if it is at the beginning of an equation number, if it is moved to the other side of the equal sign, than it turns the opposite charge. Hope this answers your question :)
Look at the photo above and Answer the following
First one will get brainliest
Points set to 15 pls answer this as fast as possible grade 9 maths thank you
[tex]6 \times ( - 4) \\\blue{ = - 24}[/tex]
[tex] \\[/tex]
[tex] \frac{ - 20}{ - 5} \\ = \frac{20}{5} \\ \blue{= 4}[/tex]
[tex] \\[/tex]
[tex] \frac{ - 60}{6} \\\blue{ = - 10}[/tex]
[tex] \\[/tex]
[tex] - 2 \times 9 \\ \blue{ = - 18}[/tex]
[tex] \\[/tex]
[tex] \frac{20}{ - 4} \\ \blue{ = - 5}[/tex]
[tex] \\[/tex]
[tex] - 2 \times - 5 \\ \blue{= + 10}[/tex]
[tex] \\[/tex]
[tex] \frac{ - 49}{7} \\ \blue{ = - 7}[/tex]
[tex] \\[/tex]
[tex] - 10 \times - 7 \\ \blue{= + 70}[/tex]
[tex] \\[/tex]
[tex] \frac{36}{ - 6} \\ \blue{= - 6}[/tex]
[tex] \\[/tex]
[tex] - 10 \times 8 \\ \blue{ = - 80}[/tex]
[tex] \\[/tex]
[tex](2 \times - 3) - ( - 7\times - 10) \\ = - 6 - ( + 70) \\ = - 6 - 70 \\ \blue{ = - 76}[/tex]
please answer the question hurry up get 25 point
Answer:
[tex]x = - 1.[/tex]
Step-by-step explanation:
[tex] {2}^{x} = \frac{1}{2} \\ {2}^{x} = {2}^{ - 1} \\ x = - 1.[/tex]
♨Rage♨
Step-by-step explanation:
Hey there!
Given;
[tex] {2}^{x} = \frac{1}{2} [/tex]
We know that (1/2) can be written as 2^-1. So, it will be;
[tex] {2}^{x} = {2}^{ - 1} [/tex]
Looking on both sides we find that both have same base. So,
x = -1
(Note: While solving the exponential equation you must make base same by simplifying them and then equate the power)
Hope it helps...
MY 1st QUESTION, WILL GIVE BRAINILIST!
Scott's retirement party will cost $8 if he invites 4 guests. What is the maximum number of guests there can be if Scott can afford to spend a total of $14 on his retirement party? Solve using unit rates.
7, because 8/4 = 2 which means that 1 guest = $2. So if we do 14 / 2 to see how many guests that would be, it's 7.
Answer:
7
Step-by-step explanation:
Well if it's $8 for 4 people then you have to divide to get the rate:
$8/4 = [tex]\frac{2}{person}[/tex]
now you can divide the disired amount to get the number of people:
$14/ [tex]\frac{2}{person}[/tex] = 7 people
were asked whether they like cricket (C) and football (F). The number liking both cricket and football was three times the number liking only cricket. Adding 3 to the number liking only cricket and doubling the answer equals the number of people liking only football. Four said they did not like sport at all.
a Draw a Venn diagram to represent this information. b Calculate n(C ∩ F).
c Calculate n(C ∩ F').
d Calculate n(C ' ∩ F).
Plzzzz help me
Find the length of AB if AC = 18 and BC = 7.
Suppose jefferson middle school had 616 students and averaged 28 students per teacher during the year. If Jefferson Middle Schools student population increases by 18% this year and 9% of last years teacers left, how many new teachrs does Jefferson need to hire to keep its average of 28 students per teacher
Answer:
6 more teachers are required.
Step-by-step explanation:
Total number of students = 616
No of teachers = 616/28= 22
Increase in students = 18%
= 18/100*616= 110.88= 111
Total number of students = 616+111= 727
Decrease in teachers = 9%
= 9/100*22= 1.98= 2
New number of teachers= 20
Now Average is 28 students per teacher so
727/28= 25.96= 26 teachers are required for the total number of 727 students. The school has already 20 teachers so they need 6 more teachers.
4. What is the solution of the proportion 3 16 = 9 y ?
answer:
5.33333333333
-1/4 multiplied by 1 1/2
Answer:
[tex]-0.375[/tex]
For more help, take a look at this chart.
Hi if you can answer this i'll mark u brainllest and give you MORE points
How can you work backward from 1/3 to check the answer when converting 0.3 as a fraction?
Pls I really need help with this
B is the answer.............
What is 12% of 504 please let me know
Answer:
504 * 0.12 = 60.48
Step-by-step explanation:
math
Answer:
its 60.48
Step-by-step explanation:
Convert 12% to a decimal which is 0.12
then do the sum 0.12x504
Which two steps will complete the list correctly?
O4. Divide the original measurement by the conversion factors
5. Check for reasonableness.
O4. Multiply the original measure by the conversion factors.
5. Simplify the answer
O4. Multiply the original measure by the conversion factors.
5. Check for reasonableness.
4. Divide the original measure by the conversion factors
5. Sinplify the answer
Answer:
the 3 one xD
Step-by-step explanation:
i know i am bulted D I F F E R E N T ~(T-T)~
Jonathan forgot his math homework on the kitchen table and left for school without it. He biked at the speed of 15 mph. His mother saw the homework when he was already 1 mile from home, and started chasing him. She drove at a speed of 25 mph and caught him at the school entrance. How far is the school from Jonathan's home?
Answer:
The school is 1.5 miles away from Jonathan's home
Step-by-step explanation:
Let D be the distance remaining after 1 mile
We are given that He biked at the speed of 15 mph. His mother saw the homework when he was already 1 mile from home, and started chasing him. She drove at a speed of 25 mph and caught him at the school entrance.
So, Time taken to cover D distance by Son is equal to the time taken by mother from home to school entrance(D+1) since she caught him at school entrance
Speed of Jonathan bike = 15 mph
Speed of Mother's bike = 25 mph
So, [tex]\frac{D}{15}=\frac{D+1}{25}[/tex]
25D=15D+15
10D=15
D=1.5
So, the school is 1.5 miles away from Jonathan's home
Evaluate 2√2/(√2-√3)
Why does the author of this
historical fiction story include the
detail that Bass Reeves couldn't
read?
It shows that Reeves could creatively
work around his disadvantages.
It shows that Reeves had no time for
reading books on his travels.
It shows that Reeves faced dangerous situations because of his job.
It shows that Reeves preferred to work
alongside other lawmen
PLEASE HELP I WILL PUT BRAINLIEST
Answer:
It’s it shows that Reece could work around his disadvantages
Step-by-step explanation:
Can anyone help with this one ?
Answer:
1. 35 2. 145 3. 35 4. 90 5. 145
Step-by-step explanation:
please find the answer, i need this asap!
Answer:
the correct answer is 2
Step-by-step explanation:
Answer: x=2
Step-by-step explanation:
Anyone help me out plz show work I need it now anyone!!
Answer:
3x2 - x + 10 when x=-4 plug in -4 for x 3(-4)^2 -(-4)+10
3(16)+4+10
3x16= 48
48+4+10= 62
Suzie's work is incorrect because of her negative distributions
Step-by-step explanation:
What is the app, oximate value of 8
to the nearest tenth?
Answer:
10
Step-by-step explanation:
All other tens values are too far
Answer:
10
Step-by-step explanation:
Simplify: 3x-4(2x-6) + 9
g(t) = -4t + 2; Find g(6)
Answer:
g(6)=-22
Step-by-step explanation:
g(6)=-4(6)+2
g(6)=-24+2
g(6)=-22
Q3. Kylie sits two maths test. She scores 19/25 in the first one, and 16/20 in the second one.
Which test has she done better in?
Answer: Kylie did better in the second one than she did in the first one
Step-by-step explanation:
If you do 19 divided by 25 you will get 0.76 so she got a 76% on the first test. Then if you do 16 divided by 20 you will get 0.8 so she got a 80% on the second test.
A power boat travels along a river in which the flow of water is at a constant in one direction. If the boat travels at 40 mph downstream and 30 mph upstream. What is the speed of the boat in still water and the speed of the river?
Answer:
speed of boat is 35 mph
speed of river is 5mph.
Step-by-step explanation:
Let the speed of boat be u mph
let the speed of river be v mph
When boat travel downstream
in that case flow of river will support the speed of boat hence
speed of river will be added to speed of boat
Thus,
speed of boat in downstream = speed of boat + speed of river = u + v
Given
the boat travels at 40 mph downstream
thus,
u + v = 40 -----1
When boat travel upstream
in that case flow of river will oppose the speed of boat hence
speed of river will be subtracted from speed of boat
Thus,
speed of boat in downstream = speed of boat -speed of river = u - v
Given
the boat travels at 30 mph upstream
thus,
u - v = 30 ----2
adding 1 + 2
we have
u + v = 40
+ u - v = 30
2u = 70
u = 70/2 = 35
Thus,
speed of boat is 35 mph
using u = 35 in u + v = 40
we have
35 + v = 40
v = 40 - 35 = 5
Thus, speed of river is 5mph.
Point S is the _ of UT?
Answer:
VStep-by-step explanation:
SV is correct because it is the same
length of UT. You can check by using
your fingers to check the length of
UT then turn the picture around to
see if it is equal.
Hope this helps! <3
Answer:
S is the midpoint of UT
Step-by-step explanation:
US = ST -----> from the picture
So, S is the mid point