Question

solve for x : x^2-9/x+3=4/7

Answer 1

Given problem is :      ( x²  - 9) / (x + 3)  = 4 /7

Cross multiply the terms:
    7 x² - 7*9 = 4x + 4*3
    7 x² - 4 x - 75 = 0
                                     7 * 3 * 5 * 5  = 21 * 25  difference is 4
    7 x² - 25 x + 21 x - 75 = 0
    x (7x - 25) + 3 (7 x - 25) = 0
     (x + 3) (7 x - 25) = 0

    x = -3    or    x = 25/7

Answer 2

Heya user,

---> [ x² - 9 ] / [ x + 3 ] = 4 / 7
==> 7[ x + 3 ][ x - 3 ] = 4 [ x + 3 ]
==> 7 [ x + 3 ][ x - 3 ] - 4 [ x + 3 ] = 0
==> [ x + 3 ] [ 7x - 21 - 4 ] = 0
==> [ x + 3 ] = 0 ------------ or ----------- [ 7x - 25 ] = 0
==> x = -3 or 25/7 <--- Desired Result...