Find the values of a and b
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(make sure to show your work)

The required values are a = 29°, b = 20°

Step-by-step explanation:

Angles and Lines

The image shows two lines crossing at a point where three angles are marked: 57°, 7b-17, and 2a-1.

It can be noted that 57° and 7b-17 are linear angles whose sum is 180°:

57° + 7b - 17° = 180°

Solving for b:

7b = 180° + 17° - 57°

7b = 140°

b = 140°/7 = 20°

b = 20°

It can also be noted that 57° and 2a-1 are vertical angles (opposite angles). Vertical angles are congruent, thus:

57° = 2a - 1°

Adding 1:

2a = 58°

a = 29°

The required values are a = 29°, b = 20°

the correct is answer is a 9-sided polygon!

circumference divided by 3.141592654 then timesthe radius twice

step-by-step explanation:

circumference divided by 3.141592654 then timesthe radius twice