Question

solve this question​

Answer 1

Question :-

Solve for x : $\sf \frac{ {x}^{2} - 9 }{x + 3}$

Answer

$\sf \frac{ {x}^{2} - 9 }{x + 3} = \frac{4}{7}$

$\sf = 7( {x}^{2} - 9) = 4(x + 3)$

$\sf = 7 {x}^{2} - 63 = 4x + 12$

$\sf = 7 {x}^{2} - 63 - 12 - 4x = 0$

$\sf = 7x^2 - 4x - 75 = 0$

By splitting middle term :-

$\sf 7x^2 - 4x - 75 = 0$

$\sf 7x^2 + 21x - 25x - 75 = 0$

$\sf 7x (x+3) - 25(x+3) = 0$

$\sf (7x-25)(x+3) = 0$

Value of x :-

$\sf 7x - 25 = 0$

$\sf 7x = 25$

• $\sf x = \frac{25}{7}$

$\sf x+3 = 0$

• $\sf x = -3$

$\boxed{\sf x = \frac{25}{7} , -3}$