Question

The figures below are similar. What are a) the ratio of the perimeters and b) the ratios of the areas of the larger figure to the smaller figure? The figures are not drawn to scale.

http://gyazo.com/53b9d9f3f176ae4b195f5cd8c431505f

My answer: I know that a part of it is 5/12 but I don't know what else. It's either going to be 25/4 or 7 over 4.

Answer 1

I just need to know.

Answer 2

@Hero

Answer 3

2.) Find the area of the shaded region. Leave your answer in terms of and in simplest radical form.

http://assets.openstudy.com/updates/attachments/4fced66ee4b0c6963ad9ec74-kaitlinlikesmusic-1338955382935-shaded.png

My answer: 120 pi -36sqrt3. Is that correct?

Answer 4

@phi @amistre64

Answer 5

@mathmate

Answer 6

@radar

Answer 7

@EclipsedStar

Answer 8

for the similar figures with length 30 and 12
the ratio of perimeters would be 30/12 or 5/2

Answer 9

@Lollygirl217 For the first question, remember that the area of two similar polygons is proportional to the squares of the ratio between them.

Answer 10

the areas will be the in the square of the lengths
25/4

(an amazing property that holds for similar shapes)

Answer 11

Oh mk.

Answer 12

area of circle - area of segment

area of segment is area of sector - area of triangle
so
A(circle) - (A(sector) - A(tri))= A(circle) - A(sector) + A(triangle)

Answer 13

the area of the sector is 1/6 of the whole circle so
A(circle) - A(sector) is A(circle) - A(circle)/6 = 5 A(circle)/6

so we want
5 A(circle)/6+ A(triangle)

Answer 14

area of the circle is 144 pi
5/6 *144 pi is 120 pi

A(tri) is 36 sqr(3)
so the area we want is
120 pi + 36 sqr(3)

Answer 15

Thanks again. xD