Question

What is the y-coordinate for the solution to the system of equations?

{y=1/2x−4
{y=−2x+1

Answer 1

y = -3

Explanation:

{y = x/2 - 4

y = 1 - 2 x

Substitute y = x/2 - 4 into the second equation:

{y = x/2 - 4

x/2 - 4 = 1 - 2 x

In the second equation, look to solve for x:

{y = x/2 - 4

x/2 - 4 = 1 - 2 x

Add 2 x + 4 to both sides:

{y = x/2 - 4

(5 x)/2 = 5

Multiply both sides by 2/5:

{y = x/2 - 4

x = 2

Substitute x = 2 into the first equation:

{y = -3

x = 2

Collect results in alphabetical order:

Answer:

{x = 2

y = -3