For the following system, use the second equation to make a substitution for y in the first equation. 2x + y = 6 y = 3x + 4 What is the resulting equation?

Question

 y + 2x + y = 6
2x + y + 3x + 4 = 6
2x + (3x + 4) = 6

are the answer choices

Answer 1

2x + y = 6              eq1

y = 3x + 4              eq2

 

 

Substitute eq2 into eq1.  This will make eq1 in terms of x rather than both x and y.

 

2x + (3x + 4) = 6