Answer:
Solution given:
The area of a circle =80.86cm²
we have:
The area of a circle =πr²
substituting value of area of circle we get
80.86cm=3.14*r²
dividing both side by 3.14
80.86/3.14=3.14*r²/3.14
25.75=r²
doing square root on both side

r=5.07cm
<u>The</u><u> </u><u>length</u><u> </u><u>of</u><u> </u><u>radius</u><u> </u><u>is</u><u> </u><u>5</u><u>.</u><u>0</u><u>7</u><u>cm</u>
I belive is B hope that helped
Answer:
6.2
Step-by-step explanation:
Although there's multiple ways to solve this problem, my method will be to simply find the area for the full triangle (the empty + orange triangles) and subtract the area of the smaller, empty triangle.
Now, you that area for a triangle is 1/2*base*height.
To find the measurements for the full triangle, you must add up the bases for the two smaller triangles:

Height is the same for both triangles so Height total = 4 ft.
Now the total area can be calculated:
Area total= 1/2* base_total * height_total
Area total = 1/2 * 5ft * 4 ft
Area total = 20 / 2 = 10 ft squared
Lastly, subtract the area of the empty triangle from the total triangle to find the orange triangle.
Area Empty Triangle = 1/2 * base_empty * height_empty
Area Empty Triangle = 1/2 * 1.9ft * 4 ft = 7.6 ft / 2 = 3.8 ft squared
Area total - Area empty = 10ft^2 - 3.8ft^2 = 6.2 ft squared
Answer:
A shopkeeper marks:
$200 * 1.4 = $280
Step-by-step explanation:
With a discount of 25%:
$280 * 0.75 = $210
Smart Dot, multiply the cost per hour by number of hours (t) and add to the monthly fee:
C = 0.50t + 12
Communication plus: Multiply the cost per hour by number of hours (t)
C = 2.50t