For the perimeter you have to consider the EXTERNAL SHAPE ONLY:
a) the perimeter of half a circle WITHOUT ITS DIAMETER is:
π.R - 2R → 3.14x1.5 - 2x1.5 → 1.71 cm
b) the perimeter of the rectangle WITHOUT THE UPPER SIDE is:
2.5+3+2.5 = 8 cm
Hence the perimeter of the figure is 1.71 + 8 = 9.71 cm
2) Area of the figure:
Area of half circle is π.R²/2 →3.14 x (1.5)²/2 → Area half circle = 3.5325 cm²
Area of rectangle = 2.5 x 3 = 7.5 cm²
Total area = 3.5325 + 7.5 = 11.0325 ≈ 11 cm²
The answer is 2160. Do you need the steps ?
Answer:
Yes
Step-by-step explanation:
The formula for area of a triangle is A = (1/2)bh,
For the first triangle we can leave it in general terms, so it's area is
A = (1/2)bh, depending on what b and h are, but it doesn't matter here...
The second triangle has base that is twice the other triangles base. Bases being multiples of each other is the definition of being proportional so the bases are proportional, an the area of the second triangle is
A = (1/2)(2b)h, which simplifies to
A = bh
Comparing the 2 areas, you can see that one has a multiplier of (1/2), so their areas are proportional
