Question

Find the roots of the quadratic equation if they exist by Completely the square -4x² – 7x +12 = 0

Answer 1

I think that is the ans. (-7±√241)/8.  

Answer 2

Answer:

x = ( -7 ± √241 )/8

Step-by-step explanation:

Given Quadratic equation ,

-4x²-7x + 12 = 0

Divide each term with -4 , we get

=> x² + ( 7/4 )x - 3 = 0

=> x² + 2.x.(7/8 ) = 3

=> x² + 2.x.(7/8 )+ (7/8)² = 3 + (7/8)²

=> ( x + 7/8 )² = 3 + 49/64

=> ( x + 7/8 )² = ( 192 + 49 )/64

=> ( x + 7/8 )² = 241/64

=> x + 7/8 = ± √(241/64)

=> x = -7/8 ± √241/8

=> x = ( -7 + √241 )/8

Or x = ( -7 - √241 )/8

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