Question 7
<h3>Answer: A) 15</h3>
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Work Shown:
angle B = angle D = 56
angle C = angle F = 64
The missing angle A adds with B and C to get 180
A+B+C = 180
A = 180-B-C
A = 180-56-64
A = 60
Since angles B and D are congruent, and C and F are congruent, this must mean angle A = angle E. I'm using the angle angle (AA) similarity rule.
angle E = angle A
3x+15 = 60
3x = 60-15
3x = 45
x = 45/3
x = 15
Side note: I'm not sure why your teacher marked angle E as the same as angles C and F. They should have used another angle marker to indicate that angles A and E are the same.
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Question 8
<h3>Answer: B) 17</h3>
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Work Shown:
Triangle ABC is congruent to triangle EDF. The order is important. We have A first, then B, then C for ABC. Also, we have E first, then D, then F for EDF.
Therefore, we have these three pairings
- angle A = angle E
- angle B = angle D
- angle C = angle F
We'll first need angle C
A+B+C = 180
C = 180-A-B
C = 180-42-108
C = 30
which we'll then solve for x
angle F = angle C
4x-4 = 30
4x = 30+4
4x = 34
x = 34/4
x = 8.5
which doubles to
2x = 2*8.5
2x = 17
