which equation has a qraph with no y intercept

Question

mendicant_bias · Answer

Is there anything listed? Or is that all it says?

anonymous · Answer

a) y=3
b) x=5
c) y=-x
d) x=y

mendicant_bias · Answer

Okay, let's get an idea of what these look like. If you just plugged in values at x = 0, if x is a variable, you should be able to find if it has a y-intercept. So, take all of those equations, and if there is an x variable in it, plug in for zero, and tell me what you find.

anonymous · Answer

okay

anonymous · Answer

c?

mendicant_bias · Answer

No, not an answer. Just plug into the equations for x= 0, and tell me what you get from each equation.

anonymous · Answer

im confused

mendicant_bias · Answer

No problem. I'll demonstrate. So, at the point that x = 0, you will have a y-intercept, if there is one at all. For these equations, you can put zero in the place of where x is to find out the value of y at that point, like so:
$$y|dw:1366920493563:dw| = 5$$$$y = -x$$$$x = y$$
$$y = 3 $$$$0 = 5$$$$y = 0$$$$0 = y$$ From these equations, you can find out a few things. See the ones where x equals a number? Those are straight lines where no matter what you put in for x, the y-value will always be 5. It's just a horizontal line across the graph, like this:

mendicant_bias · Answer

So, if you ever have x = a number, you know that it definitely has a y-intercept, which is (whatever that number is). Whenever you have y equaling x and x is zero, you know that there's a y-intercept. The only time you will ever find an equation without a y-intercept in these cases is when you have y =  a number, no variable, nothing, just a number, like y = 3. In this case, it just forms a vertical line like this:|dw:1366920690065:dw|

anonymous · Answer

ty so much for your patience, I am trying to help my daugter learn this and we are both struggling.

mendicant_bias · Answer

No problem.

mendicant_bias · Answer

Just ask me if you have any other questions.

anonymous · Answer

ty so much!! we are tying to get her ready for her ECA test and she is stressd. Teacher wont let them bring home book!!

mendicant_bias · Answer

No worries.

anonymous · Answer

we have a couple more but we are working on the others she understands first, are u going to be here for a little while?

mendicant_bias · Answer

Yeah, i'll be here. But do you understand what the answer to the first one is? Let me ask, what do you guys think it is?