What are the intercepts of the line 2y=-x+1?

2 Answers
Oct 16, 2015

I found:
(1,0)
(0,1/2)

Explanation:

x-intercept:
set y=0
you get:
0=-x+1
so x=1

y-intercept:
set x=0
you get:
2y=1
so y=1/2

Oct 16, 2015

( x, y ) -> ( 0, 1/2) " and " (1, 0 )

Explanation:

The final answers are at parts ( 2 ) and ( 3 )

Before you can determine the intercepts you need to manipulate the equation so that you only have y on the left hand side of the equals sign and everything else on the other side.
To isolate y and still maintain balance multiply both sides by 1/2

Step1. " " 1/2( 2y) = 1/2(-x+1)

2/2 y = -1/2 x + 1/2

But 2/2 = 1 giving;

y= -1/2x + 1/2 .........................( 1 )

Now to find the intercepts:

.*******
Step2. The graph crosses the x-axis at y=0

Substitute y=0 in (1) giving:

0 = -1/2x + 1/2

Add 1/2x to both sides so that you may part isolate x

( 0 ) + 1/2x =(-1/2x+1/2) + 1/2x

1/2x=1/2

Multiply both sides by 2 giving:

x=1
so one of the points where it crosses is at y=0 , x =1 ......( 2 )

.**********
Step3. The graph crosses the y-axis at x=0

Substituting y = 0 in equation ( 1 ) gives:

y = 1/2 ....................( 3 )
so the other point where it crosses is at y=1/2, x=0 .......( 3 )