Question

If 3 is the root of x2+kx-24=0 it also a root of

Answer 1

Answer:

- 8

Step-by-step explanation:

f(x) = x² + kx - 24

3 is one root of the equation

=> (3)² + 3k - 24 = 0

=> 3k - 15 = 0

=> 3k = 15

=> k = 5

Thus the quadratic equation is x²+ 5x - 24 = 0

x²+ 8x - 3x - 24 = 0

x(x+8) -3(x+8) = 0

(x+8)(x-3) = 0

x = -8 and 3.

Thus the other root is - 8.

Answer 2

Answer:

${x}^{2} + kx - 24 = 0$

it is a quadratic equation and it is given that 3 is the root of it.

Step-by-step explanation:

we will put 3 in place of x in this equation so as to get the value of k.

3^2 + k(3) -24 = 0

9 +3k -24 = 0

3k - 15 = 0

3k = 15

k = 15/3

k = 5

so the equation is

{x}^{2} + 5x - 24 = 0

now we will find the second root of it

x^2 + 8x - 3x - 24 = 0

x (x - 8) -3 (x - 8) = 0

(x - 3) (x - 8) = 0

x-3 =0

x = 3

x - 8 = 0

x = 8

the other root of this equation is 8.