Question

Solve the system using substitution. 2x + y = 7 x - y = 5 What is the solution for x? -4 -1 1 4

Answer 1

Answer:

x = 4

Step-by-step explanation:

Given the 2 equations

2x + y = 7 → (1)

x - y = 5 → (2)

Rearrange (1) expressing y in terms of x by subtracting 2x from both sides

y = 7 - 2x ← substitute into (2)

x - (7 - 2x) = 5

x - 7 + 2x = 5, that is

3x - 7 = 5 ( add 7 to both sides )

3x = 12 ( divide both sides by 3 )

x = 4