Use FOIL method... ( First Outer Inner Last )
Solution:
(2b+1) (3b-2) = 55
First, 2b x 3b = 6b²
Outer, 2b (-2) = -4b
Inner, 1 x 3b = 3b
Last, 1 (-2) = -2
6b²-4b+3b-2
Then add the two numbers between them ( the -4b and the 3b )
-4b+3b = -12b
And...
6b²-12b-2 = 55 - 55
Final answer is;
6b²-12b-2 = 0
