Question

Factorise 3x^2-4x-24 by y + 4

Answer 1

x  = (2 + 2√19)/3 or (2 - 2√19)/3  

Step-by-step explanation:

The solution for a Quadratic equation is found by the formula:  

x = [-b +- √(b² - 4ac) ] / 2a

where ax² + bx + c = 0  is the equation and a and b are the respective co-efficients of x² and x, and c is the constant.  

To solve 3x² -4x -24 = 0

a = 3

b = -4

c = -24

b² - 4ac = 16 - (-288) = 304

√b² - 4ac = √304 = √2^4 * 19 = 4√19

Therefore x = (4 +- 4√19) / 6

x = (4 + 4√19) / 6  or (4 - 4√19) / 6

x  = (2 + 2√19) / 3 or (2 - 2√19) / 3  

 x  = 3.573 or -2.239