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3 votes
The measures of the angles of △ABC are given by the expressions in the table.

Angle Measure
A ​​ (12x + 12)°
B 15°
C (3x + 18)°

What are the measures of angles A and C?



Enter your answers in the boxes.

​ m∠A= ​



​ m∠C= ​

2 Answers

6 votes

Answer:

m∠A=​120 º

​m∠C=45 º

Explanation:

Hope this helps :)

User Horsh
by
6.7k points
4 votes
First you need to find x, and you can do this by creating an equation because you know that angles in a triangle add up to 180°, so:
12x + 12 + 15 + 3x + 18 = 180
15x + 45 = 180
- 45
15x = 135
÷ 15
x = 9
Now you can substitute it in.
Angle A = (12 × 9) + 12 = 108 + 12 = 120°
Angle C = (3 × 9) + 18 = 27 + 18 = 45°
I hope this helps!
User Arpad Bajzath
by
5.7k points