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Find a quadratic equation in X whose roots are -2 and 3/4​

2 Answers

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The quadratic formula states that the roots of the equation ax^2 + bx + c = 0 are given by (-b ± √(b^2 - 4ac))/(2a). To find a quadratic equation whose roots are -2 and 3/4, we can set these values equal to (-b ± √(b^2 - 4ac))/(2a) and solve for the values of a, b, and c.

One such equation is (x+2)(x-3/4) = 0. Expanding this product, we get x^2 - x/2 + 3/8 = 0

Another equation is x^2 - 4x + 8 = 0 (by Vieta's Formulas)
User Peter Cock
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4 votes

Answer:

4x² + 5x - 6 = 0

Explanation:

Quadratic equation:


\boxed{x^2-(sum \ of \ roots)x+product \ of \ roots=0}


Sum \ of \ roots = -2 + (3)/(4)


= (-2*4)/(1*4)+(3)/(4)\\\\=(-8)/(4)+(3)/(4)\\\\=(-5)/(4)\\\\


\sf product \ of \ roots =-2 *(3)/(4)


=(-6)/(4)

Quadratic equation:


x^2 - \left((-5)/(4)\right)x+\left((-6)/(4)\right)=0

Multiply the entire equation by 4,

4x² - (-5)x + (-6) = 0

4x² + 5x - 6 = 0

User Benjamin Ziepert
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