Question

If 4 is a root of quadratic equation x square + ax - 8=0 then find a

Answer 1

Step-by-step explanation:

x^2 × ax - 8 = 0

4^2 × ax - 8 =0

16 × 8x - 8 =0

8x = -8

x = -8/8. = - 1

Answer 2

Answer:

-2

Step-by-step explanation:

given equation is $x^{2}$ +ax-8 -----(1)

four is a solution of equation,

therefore, x=4

putting value of x in eq. (1)

= (4)^2 + a(4) - 8

=  16 + 4a -8

=  4a+8 =0

=   4a = -8

=    a=  -8/4

=     a = -2