Multiplying Expressions with Parentheses
Example:
First, use the distributive law and distribute the first factor over the second:
(a + b) (c + d)
= (a + b) c + (a + b)d |
Now, distribute the c over (a + b):
(a + b) c + (a + b)d
= ac + bc + (a + b)d |
Finally, distribute the d over (a + b):
ac + bc + (a + b)d
= ac + bc + ad + bd |
So, we have found out:
(a + b) (c + d)
= ac + bc + ad + bd |