Question
Solve the following quadratic equation by factorization method
$4 x^2-7 x-2=0$
$4 x^2-7 x-2=0$
✓
Answer
$4 x^2-7 x-2=0$
$4 x^2-8 x+x-2=0$
$4 x(x-2)+1(x-2)=0$
$(x-2)+(4 x+1)=0$
x – 2 = 0 or 4x + 1 = 0 ......(equate the product of factors to zero)
$x=2 \text { or } 4 x=-1 \Rightarrow x=\frac{-1}{4}$
The roots are $2 ; \frac{-1}{4}$
$4 x^2-8 x+x-2=0$
$4 x(x-2)+1(x-2)=0$
$(x-2)+(4 x+1)=0$
x – 2 = 0 or 4x + 1 = 0 ......(equate the product of factors to zero)
$x=2 \text { or } 4 x=-1 \Rightarrow x=\frac{-1}{4}$
The roots are $2 ; \frac{-1}{4}$
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