Answer:
See explanation
Step-by-step explanation:
16. Two parallel lines are cut by transversal. Angles with measures
and
are alternate exterior angles. By alternate exterior angles, the measures of alternate exterior angles are the same:

Then

17. Two parallel lines are cut by transversal. Angles with measures
and
are alternate interior angles. By alternate interior angles, the measures of alternate interior angles are the same:

Then

18. Two parallel lines are cut by transversal. Angles with measures
and
are alternate exterior angles. By alternate interior angles, the measures of alternate exterior angles are the same:

Then

19. The diagram shows two complementary angles with measures
and
. The measures of complementary angles add up to
then

Hence,

Check:

20. Angles
and
are vertical angles. By vertical angles theorem, vertical angles are congruent, so

Hence,

21.
and
are supplementary. The measures of supplementary angles add up to
so

Therefore,

Answer: D
Step-by-step explanation:
4r-r+3r can be simplified to just 6r
-s-2s-s can be simplified to just -4s
Answer:
A. 14,000
Step-by-step explanation:
because 673 rounded would equal 700
and 18 rounded would be 20
so 700x20 would be 14,000
hopefully you understand
and i hope you have a good day :)
Answer:
-675
Step-by-step explanation:
The sum can be broken into parts that you know. Here, one of those parts is the sum of numbers 1 to n. That sum is given by n(n+1)/2.

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Another way to do this is to realize the sequence of numbers is an arithmetic sequence with a first term of 65 and a last term of 67-2·75 = -83.
The sum of an arithmetic sequence is found by multiplying the number of terms by their average value. Their average value is the average of the first and last terms.
The average value of those 75 terms is (65 +(-83))/2 = -9, so their sum is ...
75(-9) = -675
S + 4t = r
subtract 4t from both sides
s = r - 4t answer