Question

Use the substitution method to solve the system of equations.

4x – y = 4
x + 4y = 18

Answer 1

(1, 4) /
(4, 2) /
(4, 1) /
(2, 4)

Answer 2

solve the first for either y or x
say we solve for y
now plug that y into the second equation where there is y and solve that equation for x
and then go back to the first equation that you solved for y and plug the x you just found wherever there is an x

Answer 3

\[-y=4-4x => y=-4+4x\]
see i solved the first equation for y

Answer 4

now plug this in wherever you have a y in the equation and solve for x

Answer 5

\[x+4(-4+4x)=18\]
solve this for x

Answer 6

You know it would be best not to post the same question twice. Thanks.

Answer 7

after solving for x, we get x=2