# SOLUTION: what is the y-intercept for x^2-2x-8

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 Question 70015: what is the y-intercept for x^2-2x-8Found 2 solutions by tutorcecilia, bucky:Answer by tutorcecilia(2152)   (Show Source): You can put this solution on YOUR website!what is the y-intercept for x^2-2x-8 The y-intercept is the point where the parabola crosses the y-axis. This value will always be (0, b) where x=0 (if there is a y-intercept). . So, let x=0 and solve for y: y=x^2-2x-8 y=(0)^2-(0)-8 y=-8 or point (0, -8) Answer by bucky(2189)   (Show Source): You can put this solution on YOUR website!Set y equal to the function you were given. This results in the equation: Now think about the general structure of a graph. If you have a point on the Y-axis, what is the value of X for that point. Every point on the Y-axis has a corresponding X value of zero!!! Think of +3 on the Y-axis. This would be the point (0,+3). Similarly the point -5 on the Y-axis would be (0, -5) and so on. So for the above equation we can simply set x equal to zero to find the corresponding value of y that satisfies the equation. Start with: Plug in zero for x. This causes the terms that contain an x to be zero. What you are left with is: which simplifies to just The Y-intercept occurs at y = -8 or at the point (0,-8). It's harder to explain than it is to just set x equal to zero and determine what is left on the right side of the equation. Hope this helps you understand how to find Y intercepts.