could someone help me with this ? i need to find m
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the three angles of a triangle always add up to 180 degrees.
So, add the three angles together!
2x - 12 + 2x + 17 + 9x - 7 = 180
Group the similar numbers together.
13x -2 = 180
13x = 182
x = 14
Plug x in to 2x + 17
14*2 + 17 = 45
mX = 45 degrees
Answer:
m∠X = 45°
Step-by-step explanation:
All angles in a triangle add up to 180°
2x - 12 + 2x + 17 + 9x - 7 = 180
13x = 180 - 17 + 12 + 7
13x = 182
x = 14°
m∠X = 2x + 17
sub x = 14° into m∠X
2(14) + 17
m∠X = 45°