Answer:
(a) 4
(b) 4 * (7+3)
Step-by-step explanation:
(a) Let's first start by prime factorizing (finding the prime factors) 28 and 12:
12: 2*2*3
28: 2*2*7
We can see here they both share a common factor of 2*2, which is 4, therefore the GCF is 4.
(b) Factor a 4 out from the equation:

This gives us:
4 * (7+3)
Answer:
30
Step-by-step explanation:
Part of a line but has 2 end point, extends in no direction. example: @
[email protected]
This expression is already simplified.