What is the y intercept of -x + </= 4

Question

I’m supposed to graph the equation -x+y≤4

when finding x intercept y=0

so I go -x+0=4

then I get -x=4

is that okay or do I need to do something to make the x positive?

Answer 1

-x + y ≤ 4

y ≤ x + 4

y-intercept is (0, 4)

slope is 1 / 1

shade everything below the line.

Answer 2

Hi Kaitlyn B.,

yes, you should always express your answer as "x = (or other symbol) value".

In other words, don't leave it in a "-x = (or other symbol) value" form!

And, in case you didn't figure it out yet, the thing you need to do is multiply both sides of your equation by -1.

By the way, when you get an equation (or inequality) in the form you did, I find it convenient to re-express in slope-intercept form. That immediately sets up an intuitive graphical situation, that will keep you from making annoying arithmetic errors as you find the solution and write it down. (It's so easy to forget to flip the inequality sign when you multiply by -1, for example!). Just sayin'.

Cheers, -- Mr. d.