Question

12. If - 4 is a root of the equation x2 + px -4 = 0 and the equation x2 + px + 9 = 0 has equal roots, then the value
of q is??
​

Answer 1

hey mate here is ur ans 》》》》》》》

given -4 is root of equation

${x }^{2} + px - 4 = 0$

putting value of x=-4

we get

$16 - 4p - 4 = 0$

so

P=3

NOW

${x}^{2} + qx + 9 = 0$

has equal roots

so

${b}^{2} - 4ac = 0$

therefore

${q}^{2} - 36 = 0$

${q}^{2} = 36$

$q = + 6 \: or - 6$

hope it helps u

✌✌✌✌✌Mark as brainlist ✌✌✌✌

Answer 2

Answer:

Explanation:

-4² + -4p - 4 = 0

16 - 4p - 4 = 0

- 4 p + 12 = 0

p = 3

b² - 4 a c = 0 since equal roots.

p² - 4 x 1 x q = 0

9 - 4q = 0

q = 9/4