Answer:
x= -12
or
x=3
Explanation:
in order to factorise the equation x² + 9x - 36
it will be expressed like this to make it a complete equation by subtracting 36 from both sides
x² + 9x - 36=0
the next step is to look for two numbers that when multiplied will give us -36 and when added together it will give us 9.
the numbers would be -3 and 12
so we have
x²-3x + 12x -36 =0
x(x-3) + 12(x-3) = 0
(x+12)(x-3)=0
we have,
x + 12 =0
x = -12
or
x-3 =0
x= 3
Therefore, the factors for x are -12 or 3.