Question

if one zero of the quadratic polynomial 2x square_8x_mis 5/2,then the other zero is

Answer 1

2x^2-8x-m=p(x)
But 5/2 is one of the zeroes of p(x)
So, p(5/2)=2×5/2×5/2-8×5/2-m
0 =25/2-20-m
m= - 15/2
So p(x) =2x^2-8x-(-15/2)
=2x^2-8x+15/2
Now we know that
$\alpha + \beta = \frac{ - b}{a} \\ \frac{5}{2} + \beta = \frac{ - ( - 8)}{2} \\ \beta = 4 - \frac{5}{2}$

Other zeroes of the polynomial will be
beta= 3/2