Question

Calculate the value of $d$ from the equation

$\frac{2d^2-d-10}{d^2+7d+10}=\frac{d^2-4d+3}{d^2+2d-15}$

• A. $-4$
• B. $2$
• C. $4$
• D. $6$

Answer 1

The correct option is C $4$

Given, $\frac{2d^2-d-10}{d^2+7d+10}=\frac{d^2-4d+3}{d^2+2d-15}$

$\Rightarrow \frac{2d^2-5d+4d-10}{d^2+5d+4d+10}=\frac{d^2-3d-d+3}{d^2+5d-3d-15}$

$\Rightarrow \frac{d(2d-5)+2(2d-5)}{d(d+5)+2(d+5)}=\frac{d(d-3)-1(d-3)}{d(d+5)-3(d+5)}$

$\Rightarrow \frac{(d+2)(2d-5)}{(d+2)(d+5)}=\frac{(d-1)(d-3)}{(d+5)(d-3)}$

$\Rightarrow 2d-5=d-1$

$\Rightarrow 2d-d=-1+5$

$\Rightarrow d=4$