<span>Simplifying
b4 = 9
Solving
b4 = 9
Solving for variable 'b'.
Move all terms containing b to the left, all other terms to the right.
Simplifying
b4 = 9
Reorder the terms:
-9 + b4 = 9 + -9
Combine like terms: 9 + -9 = 0
-9 + b4 = 0
Factor a difference between two squares.
(3 + b2)(-3 + b2) = 0</span>
It works because even if the numbers are broken apart, you are still multiplying the numbers by their values, it's only different because once broken apart, it's in expanded form instead of standard form. It also makes multiplication easier since you don't have to deal with such large numbers.
If a flight departs from Pittsburgh at 7:55 a.m. and arrives in San Diego at 9:20 a.m.,
How long is the flight?
SOLUTION
9. 20 am - 7. 55 am = 1 hour 25 mins