Answer:
6. The triangle is acute
m<P = 60
m<Q = 84
m<R = 36
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7. Claim: the three angles added together equal 180 degrees
m<J = 116 degrees
m<K = 33 degrees
m<L = 38 degrees
Explanation:
m<P = 4a + 12 = 4(12) + 12 = 60
m<Q = 7a = 7(12) = 84
m<R = 3a = 36
(4a + 12) + 7a + 3a = 180 degrees
14a + 12 = 180
14a = 168
a = 12
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m<J = 4x + 12 = 4(26) + 12 = 116
m<K = x + 7 = 26 + 7 = 33
m<L = 2x - 14 = 2(26) - 14 = 38
(4x + 12) + (x + 7) + (2x - 14) = 180 degrees
7x - 2 = 180
7x = 182
x = 26