Question

Which of the following equations shows how substitution can be used to solve the following system of equations?

Answer 1

Answer:

(3, 5)

Step-by-step explanation:

y = 2x - 1

3x + 2y = 19

In the second equation, substitute 2x - 1 in for y, since y equals 2x - 1 in the first equation. Solve for x.

3x + 2(2x - 1) = 19

3x + 4x - 2 = 19

7x - 2 = 19

7x - 2 + 2 = 19 + 2

7x = 21

7x/7 = 21/7

x = 3

Pick the first equation to solve for y since it says y =. Substitute 3 in for x.

y = 2x - 1

y = 2(3) - 1

y = 6 - 1

y = 5