Question

What is the intersection of the lines given by 2y=-x+3 and -y=5x+1? Enter the answer as an ordered pair.

Answer 1

Answer:

(-5/9, 16/9)

Step-by-step explanation:

2y = -x + 3

-y = 5x + 1

To find the intersection, you need to substitute the y-value from the second equation into the first equation.  Rearrange the second equation so that it is equal to y.

-y = 5x + 1

-1(-y) = -1(5x + 1)

y = -5x - 1

Substitute this equation into the y-value of the first equation.

2y = -x + 3

2(-5x - 1) = -x + 3

-10x - 2 = -x + 3

(-10x - 2) + 2 = (-x + 3) + 2

-10x = -x + 5

(-10x) + x = (-x + 5) + x

-9x = 5

(-9x)/(-9) = (5)/(-9)

x = -5/9

Plug this x value into one of the equations and solve for y.

2y = -x + 3

2y = -(-5/9) + 3

2y = 5/9 + 3

2y = 32/9

(2y)/2 = (32/9)/2

y = 32/18 = 16/9

The ordered pair is (-5/9, 16/9).