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Write an equation of the parabola in intercept form that passes through (-2, 0.05) with x-intercepts of -7 and -3

User Ybull
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1 Answer

5 votes

Important things you need to know:

1. x intercept = solution of the equation

2. parabola = the highest power is x²

3. "passes through" is important because you have the y intercept (it is the c in ax² + bx + c = 0)

The intercept form is y = a(x-r)(x-s), where r and s are the x intercepts (solutions) of the graph

Substitite the numbers and values you know:

y = a(x-r)(x-s)

0.05 = a(-2-(-7)) × (-2-(-3))

Then you should find a.

Rewrite the equation in the form of y = a ( x+7 )( x+3 ) where the value of a is found.

User Vcampitelli
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