How do you find the coordinates of the point of intersection for the pair of lines whose equations y=2x-1 and x+2y=8?

2 Answers
Sep 16, 2015

x = 2 and y = 3

Explanation:

y = 2x - 1 . . . .(1)
x + 2y = 8 . . . . (2)
(1) * 2 = 2y = 4x - 2 . . . .(3)
(2) - (3) = x = 8 - 4x + 2
i.e., 4x + x = 5x = 8 + 2 = 10
or x = 10 / 5 = 2
y = 2 * 2 - 1 = 3

Sep 16, 2015

I found:
x=2
y=3

Explanation:

You can use the value of y from the first equation and substitute into the second to get:
x+2(color(red)(2x-1))=8 and solve for x:
x+4x-2=8
5x=10
x=10/5=2
use this value back into the first equation to find y:
y=2*2-1=4-1=3