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form-the-quadratic-equation-if-its-roots-are-5-and-7 - Algebra

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Question

Form the quadratic equation if its roots are 5 and 7. 

Sum

Solution

Roots of a quadratic equation are 5 and  7.

Let  α = 5 and β = 7.

α + β = 5 +7 = 12 

αβ = 5 × 7 = 35 .

∴ The quadratic equation is given by . 

x2 - (α+β ) x + α β = 0

∴ x- 12x + 35 = 0

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2014-2015 (July)

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