Quadratic Trinomials 2a²-5a-12

Sagot :

Solve by factoring:

2a² - 5a - 12=0

(2x + 3) (x - 4) = 0

2x + 3 = 0             x - 4 = 0
2x = -3                  x = 4
2       2
x = -3/2

The roots are:  -3/2   and 4
you can get the answer by using the ac method or by multiplying the first and last term 

after multiplying find the numbers that can be answered by 24 (2 x 12)  you can get it by listing the possible numbers  
1 - 24= -23
2 - 12= -10
3 - 8  = -5
4 - 6  =  -2

so the answer that has the same sign and number as the middle term of the given is 3 - 8 so it will be youre numbers that will be used for factoring quadratic trinomials but its not yet finished after that you will divide both the numbers you get from the first term 

(a - 8/2)(a+3/2)

but if the number you get cannot be divided by the first term all you need to do is multiply the first term to the a or the number before the 3

so youre answer will be
(a-4)(2a+3)