SOLUTION: what is the y and x intercept of the graph function f(x)=-.20(x-7)^2+15

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Question 812761: what is the y and x intercept of the graph function f(x)=-.20(x-7)^2+15
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
The y-intercept is the point where the graph crosses the y-axis,
which is the line x=0 ,
or the y-coordinate of that point, since we know that the point has x=0 .
We know it is only one point, because a function has at most one value of y=f%28x%29 for each value of x,
so for x=0, there is just one value of y=f%28x%29 .
In other words, the graph of a function cannot cross a vertical line (like x=0 ) more than once.
system%28x=0%2Cy=-0.20%28x-7%29%5E2%2B15%29 --> y=-0.20%280-7%29%5E2%2B15%29 --> y=-0.20%2A%28-7%29%5E2%2B15%29 --> y=-0.20%2A49%2B15%29 --> y=-9.8%2B15%29 --> highlight%28y=5.2%29%29
You would know if the answer is expected to be given as
highlight%28y=5.2%29%29 or as highlight%28+%22%28+0+%2C+5.2+%29%22+%29 .

The x-intercept is the point (or points) where the graph crosses the x-axis,
which is the line y=0 ,
or the x-coordinate of that point, since we know that the point has y=0 .
system%28y=0%2Cy=-0.20%28x-7%29%5E2%2B15%29 --> 0=-0.20%28x-7%29%5E2%2B15%29-->0.20%28x-7%29%5E2=15%29-->%28x-7%29%5E2=15%2F0.20-->%28x-7%29%5E2=75-->system%28x-7=sqrt%2875%29%2C%22or%22%2Cx-7=-sqrt%2875%29%29 -->highlight%28x=7+%2B-+sqrt%2875%29%29 or highlight%28x=7+%2B-+5sqrt%283%29%29 .
The approximate values, are x=-1.66 and x=15.66
Again, you would know how you are expected to format the answer.