The correct answers are:
(D) a<span>b ll cd
(F) a</span><span>b and cd are coplanar
Explanation:
The symbol for parallel is " </span>ll ". Therefore, if we translate the given sentence, <span>ab and cd are parallel, into the Mathematical terms, we can write it as:
</span>
ab ll cd (Option D)
Where ab = line
cd = line
Furthermore, the lines ab and cd are coplanar because they form the plane. In other words, you can say that the lines ab and cd lie on the same plane. (Option F)
Hence the correct answers are:
(D) ab ll cd
(F) ab and cd are coplanar
Problem 7: Correct
Problem 8: Correct
Problem 9: Correct
The steps are below if you are curious
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Problem 7
S = 180*(n-2)
2340 = 180*(n-2)
2340/180 = n-2
13 = n-2
n-2 = 13
n = 13+2
n = 15
I'm using n in place of lowercase s, but the idea is the same. If anything, it is better to use n for the number of sides since S already stands for the sum of the interior angles. I'm not sure why your teacher decided to swap things like that.
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Problem 8
First find y
y+116 = 180
y+116-116 = 180-116
y = 64
which is then used to find x. The quadrilateral angles add up to 180*(n-2) = 180*(4-2) = 360 degrees
Add up the 4 angles, set the sum equal to 360, solve for x
x+y+125+72 = 360
x+64+125+72 = 360 ... substitution (plug in y = 64)
x+261 = 360
x+261-261 = 360-261
x = 99
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Problem 9
With any polygon, the sum of the exterior angles is always 360 degrees
The first two exterior angles add to 264. The missing exterior angle is x
x+264 = 360
x+264-264 = 360-264
x = 96
We have

To simplify it we can divide numerator and denumerator by the same number (the greatest possible is the best)

- its the simples form..
Answer: multiple the length vu the width
Step-by-step explanation: