QUADRATICS 1

Given that one of the roots of the equation 2x² + m(x+1) + 5 = 0 is 7, find m.

Solution

Substitute x=7, in the above equation.

2(7)² + m(7+1) + 5 = 0

(2x49) + (m x 8) + 5 = 0

98 + 8m + 5 = 0

8m + 5 = -98

8m = -98 - 5

8m = -103

8m = -103

8         8

m=^-103/8

Hence m=^-103/8

TRY THIS…………………………..

NECTA 2004 QN 2a

Given that one of the roots of the equation 2x² + K(x+1) + 3 = 0 is 4, find K.