Question

Does anyone know how to use the substitution method with linear equations?

Answer 1

put up a problem and i'll check it out

Answer 2

-3x + 4y = -10

x-5y = 7

THIS IS MY TEAM WORK ASSIGNMENT NOT HOMEWORK

Answer 3

I don't remember , sorry

Answer 4

I can solve this but I don't know what substitution method is!

Answer 5

HOW WOULD YOU SOLVE IT?

Answer 6

From the second equation, solving for \(x\) gives you \(x=7+5y\).

Substitute this expression for \(x\) into the first equation:
\[-3x+4y=-10~~\Rightarrow~~-3(7+5y)+4y=-10\]
Now solve for \(y\), then for \(x\).

Answer 7

I would multiply the second equation by 3 and then add two equations term by term

Answer 8

This is so dang confusing!

Answer 9

well it's the fast way

Answer 10

Ok, so far I have -11y=11? I am still working on it though.

Answer 11

Yes, that's correct so far.

Answer 12

Y= -1?

Answer 13

Yeah, now plug that into either original equation and solve for \(x\).

Answer 14

x-5(-1)= 7?

Answer 15

Does x=2?

Answer 16

Yep

Answer 17

So that would be the answer for both?

Answer 18

or is there just 1 answer?

Answer 19

-3x + 4y = -10---(1)
x-5y = 7----(2)

in equation (2)

x=7+5y---(3)

put in equation (1)

-3(7+5y)+4y=-10
-21-15y+4y=-10
-21-11y=-10
-11y=-10+21
-11y=11
y=-1

put in equation (3)

x=7+5(-1)
x=7-5
x=2

Answer 20

Ok, how do you get the x to equal 7+5y in the 1st part?

Answer 21

x-5y = 7
add both side by 5y
x-5y+5y=7+5y
x=7+5y

Answer 22

Thank all of ya'll very much! I really appreciate it!

Answer 23

My Pleasure.