Answer:

Step-by-step explanation:

Factor out 20 from the expression.

Take 20 as common.

Answer:
I would assume you're referring to this test? if so the answer is
a, d and e
Answer:
The correct answer is False
Angles ECD and CEF add to 180
40+140 = 180
So that means we have EF parallel to CD (due to the same side interior angle theorem)
--------------
Angles BCE and ECD combine to 30+40 = 70, which is congruent to angle ABC = 70 as well.
In other words, this shows angle ABC = angle BCD. Both of these angles are alternate interior angles. Since they're congruent, they lead to AB being parallel to CD.
--------------
So far we have
AB || CD
CD || EF
Using the transitive property, we can then link the two statements to say AB || EF. Think of a chain where CD is the common link. We go from AB to CD, then from CD to EF. So we can just take a single path from AB to EF.
It's like saying "P --> Q and Q --> R, therefore P --> R"