SOLUTION: If the graph of the parabola y=ax^2+bx+c opens downward and has two negative x-values for its x-intercepts, will the value for its y-intercept be positive or negative?

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: If the graph of the parabola y=ax^2+bx+c opens downward and has two negative x-values for its x-intercepts, will the value for its y-intercept be positive or negative?      Log On


   

Question 694424: If the graph of the parabola y=ax^2+bx+c opens downward and has two negative x-values for its x-intercepts, will the value for its y-intercept be positive or negative?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If the graph of the parabola y=ax^2+bx+c opens downward and has two negative x-values for its x-intercepts, will the value for its y-intercept be positive or negative?
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Draw an x/y coordinate system.
Mark two points on the negative side of the x-axis.
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The vertex must be located above the x-axis and
on a vertical line half-way between the x-intercepts.
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Sketch a vertex that is so situated.
Sketch the parabola opening downward
from that vertex.
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It can only intercept the y-axis at a negative value.
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Cheers,
Stan H.
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