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Write the quadratic equation whose roots are 2 and -5, and whose leading coefficient is 4.​

User Ktusznio
by
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1 Answer

3 votes

Answer:

4x² + 12x - 40 = 0

Explanation:

Given the roots are x = 2 and x = - 5 then

the factors are (x - 2) and (x + 5) and the product

(x - 2)(x + 5) = 0 ← expand factors using FOIL

x² + 5x - 2x - 10 = 0, that is

x² + 3x - 10 = 0 ← multiply through by 4

4x² + 12x - 40 = 0

User Chuck M
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