solve

Question

{y=x-7
{5x+2y=7
Use the substitution method.
A.(0, −7)

B.(7, 0)

C.(3, −4)

D.(−1, −8)

Answer 1

so, substitute y=x-7 into

5x+2y = 7
5x+2(x-7) = 7
...

Answer 2

soo b

Answer 3

stop guessing. Next step:

5x+2x-14 = 7
...

B works for the 1st equation, but not the second.