The greatest common factor is 10
So the given angles are supplementary (add to 180). You take the two and add them. 21x+5+37x+1. This gets set to equal 180. 58x+6=180. Subtract 6 from both then divide by 58. You get x=3
For the first one write 9 divided by 2 gives your your radius an it’s 3.5. the formula is 2 x 3.14 x radius and that gives you 21.98.
the 2nd one is 2 x 3.14 x 9 = 56.52
the 3rd is 2 x 3.14 x 5= 31.4
formula is always 2 x 3.14 (or pie) x radius
to get your radius from your diameter you do your diameter divided by 2
Explanation:
First, switch sides of an equation.

Then, you subtract by the 80 from both sides of an equation.

And finally, simplify and subtract the numbers.


Hope this helps!
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