21.3 is the correct answer.
X/2 = 3 (x= 3*2 = 6in)
6in = 30ft
Hope I become the brainliest answer
Answer:
C.
Step-by-step explanation:
Recall that the sum of the (3) interior angles of a triangle <em>must</em> equate to 180.
In other words:

Where x is our unknown angle. So, we need to solve for x.
On the left, add 55 and 20:

Subtract 75 from both sides. The left side cancels:

Therefore, the third angle is 105 degrees.
Our answer is C.
A box of donuts would cost: b = 3.84 + 0.18f
First, we have to find the total cost of the donuts.
12 x 0.32 = 3.84
Next, we need to determine the cost of the box. However, we don't know the surface area, just the cost per foot. We can multiply the number of square feet of the box by $0.18 to find the cost.
So our equation could be: b = 3.84 + 0.18f (where f is the surface area of the box in square feet)