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# If X = 1 is a Common Root of Ax2 + Ax + 2 = 0 and X2 + X + B = 0, Then, Ab = - CBSE Class 10 - Mathematics

ConceptSolutions of Quadratic Equations by Factorization

#### Question

If x = 1 is a common root of ax2 + ax + 2 = 0 and x2 + x + b = 0, then, ab =

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#### Solution

x = 1 is the common roots given quadric equation are , ax2 + ax + 2 = 0 and x2 + x + b = 0

Then find the value of ab.

Here, ax2 + ax + 2 = 0 ….. (1)

x2 + x + b = 0….. (2)

Putting the value of  x = 1in equation (2) we get

1^2 + 1+b = 0

2 + b = 0

  b = -2

Now, putting the value of  x= 1 in equation (1) we get

a + a + 2 = 0

 2a + 2 = 0

a = (-2)/2

=-1

Then,  ab = (-1) xx (-2)

= 2

Is there an error in this question or solution?

#### APPEARS IN

Solution If X = 1 is a Common Root of Ax2 + Ax + 2 = 0 and X2 + X + B = 0, Then, Ab = Concept: Solutions of Quadratic Equations by Factorization.
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