Question

If '-4' is a root of the equation x2 + ax - 4 = 0 and the equation x2 + ax + b = 0 has equal roots, the value of 'a' & 'b' are​

Answer 1

Answer:

a=3 & b= 9/4

Step-by-step explanation:

−4 is the root of x2 +ax−4=0

⇒(−4)2 +a(−4)−4=0

⇒16−4a−4=0

⇒12=4a

so a=3

x 2 +ax−b=0

⇒x 2 +3x+b=0

It has equal roots so D=0

b2 −4ae=0

9−4b=0

so b= 9/4

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So a=3 & b= 9/4  

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