SOLUTION: how do you find the quadratic egaution of a quardratic parbolia? if the parbolia is grapghed for you and they just ask for the eguation.?

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: how do you find the quadratic egaution of a quardratic parbolia? if the parbolia is grapghed for you and they just ask for the eguation.?      Log On


   

Question 125617: how do you find the quadratic egaution of a quardratic parbolia? if the parbolia is grapghed for you and they just ask for the eguation.?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
how do you find the quadratic equation of a quadratic parabola? if the parabola is graphed for you and they just ask for the equation.?
:
Look at the x intercepts, this is the point which the graph crosses the horizontal axis
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Look at this graph:
+graph%28+300%2C+200%2C+-6%2C+10%2C+-20%2C+10%2C+x%5E2+-+3x+-+10%29+
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multiply the two factors from this: (x+2)(x-5) = x^2 - 3x - 10
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The fact that the intercepts multiplied together = -10, (the y intercept) tells us
the coefficient of x^2 is 1