Vertical angles 2 and 5, 1 and 6, 3 and 8, 7 and 4
linear pair 1 and 5, 5 and 6, 6 and 2, 2 and 1, and also 3 and 7, 7 and 8, 8 and 4, 4 and 3
congruent angles - all vertical pairs are congruent angles
2 congruent to 5, 1 congruent to 6, 3 congruent to 8, 7 congruent to 4
A) Height -7 = base
B) .5 * height * base = 60
Substituting A into B
B) .5 * height * (height -7) = 60
B) .5*height^2 -3.5*height = 60
B) .5*height^2 -3.5*height -60 = 0
Using the quadratic formula:
Height = 15
Subtracting 7 gives us the base length
Base = 8
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Double-Check
.5 * 15 * 8 = 60