Question

For the following system, use the second equation to make a substitution for y in the first equation.

2x + y = 5
y + 3 = 2x
a. 2x + 2x - 3 = 5
b. 2x + 3 - 2x = 5
c. 2x + 2x + 3 = 5

Answer 1

ok since 2x + y = 5 cannot be solved you can remake it to

y=−2x+5

alright then it says
"use the second equation to make a substitution for y in the first equation."

so use this why and make it into the second equation

it will look like this

(−2x+5) + 3 = 2x

now just combine like terms and simplify and then you get your answer

hope i helped you