1) In this question, we are going to make use of the formula for the area of that sector, to find the central angle.
2) So, let's write it out an expression involving the area of a circle, the unshaded area, and the shaded one and then plug into that the given data:
Thus, the centra angle of that shaded area is 72º
9514 1404 393
Answer:
7. 91 m²
8. 56 in²
9. 105 in²
10. 135 m²
Step-by-step explanation:
The formula for the area of a triangle is ...
A = 1/2bh
where b is the base length, and h is the height perpendicular to the base.
The formula for the area of a trapezoid is ...
A= 1/2(b1 +b2)h
where b1 and b2 are the lengths of the parallel bases, and h is the perpendicular distance between them. Note that this formula is virtually identical to the triangle formula, with the triangle 'b' being replaced by (b1+b2).
__
Fill in the numbers and do the arithmetic. The result is shown in the attachment. (We have used the triangle formula for all, with b1+b2 being used for 'b' to find the area of the trapezoids.)
7. A = 1/2(14 m)(13 m) = 91 m²
8. 56 in²
9. A = 1/2(14 +16 in)(7 in) = 105 in²
10. 135 m²
