Question

If X=1 is a common root of the equations ax²+ax-1=0 and x²+x+b=0, then the value of ab is * *

1 point

-1

-2

2

1

plzzzzz tell the answer​

Answer 1

Answer:

ab = - 1

Step-by-step explanation:

f(1) = a(1)² + a(1) - 1 = 0 ⇔ 2a - 1 = 0 ⇒ a = 1/2

g(1) = (1)² + 1 + b = 0 ⇔ 2 + b = 0 ⇒ b = - 2

ab = (1/2)×(- 2) = - 1