Q74 of 82 Page 4

Solve for x:

(CBSE 2016)

Given: 

On taking LCM we get,

On cross multiplying, we get,

(3x + 4)(x + 4) = 4(x + 1)(x + 2)

3x2 + 12x + 4x + 16 = 4(x2 + x + 2x + 2)

3x2 + 16x + 16 = 4x2 + 12x + 8

- x2 + 4x + 8 = 0

x2 - 4x - 8 = 0

Now, solving the above equation by quadratic formula.

a = 1, b = -4 and c = -8

We know that roots of a quadratic equation is given by,



So,










So, we have,

x = 2± 2√3 

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