If one of the roots of the quadratic equation x2 + mx + 24 = 0 is 1.5, then what is the value of m?
Solutions of quadratic equation are:
x = ((-b) +- (sqrt(b^2 - 4ac)))/2a
One of the solution is 1.5 and a=1, b=m and c=24
So
1.5 = (-m + (sqrt(m^2 - 4(1)(24)))) / 2(1)
3 = -m + sqrt(m^2 - 96)
3 + m = sqrt(m^2 - 96)
(3+m)^2 = m^2 - 96
9+m^2+6m = m^2 - 96
9+6m = - 96
6m = -96 -9
m = - (105/6)
m = - 17.5
Is the answer -17.5?
