30x^2-11x-6 describe using the box method

STEP 1 : Find 2 numbers which -
Add to give - 11
Multiply to give - 180 (because 30*-6)

So the 2 numbers are:
9 and - 20

STEP 2 : Input these numbers into the equation -

(remember to add the x next to 9 and - 20)

STEP 3 : Split them into 2 brackets -
Factorise them out to give -

The numbers inside the brackets MUST ALWAYS BE THE SAME

STEP 4 : This is the easiest step... You just have to end up with 2 brackets -

Is from the outside of both the brackets

Is from the bracket which must ALWAYS be the same

So you end up with your

21/2 or 5/2