Ineed asap like no /> the formula for the circumference of a circle is = 2. use 3.14 for . solve the formula for r. what is the radius of a circle with a circumference of 87 ? round to the nearest tenth. a. = 2; 13.9 cm b. =2 π ; 27.7 cm c. = 2 ; 546.4 cm d. = − 2 ; 80.7 cm the formula for the area of a triangle is = ℎ /2 solve the formula for h. what is the height of a triangle that has an area of 25 2 and a base with a length of 10 ? a. ℎ = 2 ; 1.25 mi b. ℎ = 2 ; 2.5 mi c. ℎ =2/; 0.2 mi d. ℎ = 2/; 5 mi

C / (2pi) = r;  r= 13.9 cm

2A/b = h   ;  h= 5

Step-by-step explanation:

The formula for the circumference of a circle is  C = 2* pi * r.

Solving for r, we need to divide by 2 * pi on each side

C/(2* pi) = 2*pi*r/ (2* pi)

C / (2pi) = r

If the circumference is 87, we can find r by substituting into the equation.

87 / (2 * 3.14) = r

87/ 6.28 = r

13.85350318=r

Rounding to the nearest tenth

r= 13.9 cm

The formula for the area of a triangle is  A = bℎ /2  

To solve the formula for h, we need to multiply each side by 2

2*A = bh

Then divide each side by b

2A/b = bh/b

2A/b = h

If the  area  of a triangle is 25  and the base of 10 , we can substitute in to find the height.

2* 25 /10 = h

50/10 = h

5 =h

more detail

step-by-step explanation: