(7x - 23)° + (11x + 23)° = 180°
7x - 23° + 11x + 23° = 180°
18x = 180° / : 18
x = 10°
To solve 7-2a-5-14=-2+3a :
1) combine like terms: 7-19 - 2a = -2 + 3a, and then -10 = 5a
2) solve this equation for a: a = -10/5 = -2.
The solution of 7-2a-5-14=-2+3a is a = -2.
You only need to know one side, you can use , tan, sin, or cos of the angles to find the other 2 sides.
Answer:
A is correct because 1 and 3 are vertical angles.
B is correct because there are 180 degrees in a triangle. 180-65-55 = 60. Angle 2 is vertical to the third angle, so angle 2 equals 60.
C is incorrect because it is an exterior angle. Exterior angles are equal to the sum of the two isolated interior angles. 65 + 55 ≠ 60.
D is correct because 3 is an exterior angle. Exterior angles are equal to the sum of the two isolated interior angles. 65 + 55 = 120.
In review, A, B, and D are correct.
I hope this helps you =)