The radius of the semicircle is 3 in. How long is its perimeter?
Please be accurate and explain.

15.42 inches

Step-by-step explanation:

-formula : perimeter of semi circle= πr+2r

r=3 inch

π.3+2.3

=3π+6

15.425 or 6+3π

Step-by-step explanation:

If the radius of the circle is 3 inches and the diameter is double the radius, we know the diameter is 6 inches. Then we find half of the perimeter of a circle with radius 3. The perimeter formula of a cirle is 2πr. Plugging in the radius we get: 2(3)π or 6π. Then we divide by 2 as it is a semicircle and get 3π or ≈9.425. We add 6 to this and we get the answer of 15.425 or 6+3π.

3 is greater then both of those numbers

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.