Answer:
Let R be the greater radius and r be the smaller radius
A) Area of the sidewalk = R^2 - r^2 - This can be the expression
B) = 3.14
=(R^2-r^2)
=(11^2-9^2)
=(121-81)
=*40
That was the simplified expression
Answer = 3.14 * 40 = 125.6m^2
Step-by-step explanation:
Answer:
Option A is correct.
Step-by-step explanation:
The height of the rectangular pack is h1 = 4r
The height of the parallelogram = 2r + the height of equilateral triangles with a side of 2r
The height of equilateral triangle with a side of 2r = (side)/2*√3
=(2r)/2 *√3 = r√3
The height of the parallelogram h2 = 2r+r√3 = r(2+√3)
So,the ratio of h1 to h2 is :
4r : r(2 +√3)
Cancelling r we get
Hence, the ratio is 4 : 2 +√3
Answer:
7,13,31,85,247......
Step-by-step explanation:
Step-by-step explanation:
the area of a triangle is
baseline × height / 2
the baseline (where the height hits at a 90° angle) is 4 m.
the height is 3.7 m.
so, the area is
4 × 3.7 / 2 = 2 × 3.7 = 7.4 m²
