Question

Two triangles are similar and have a ratio of similarity of 1:5. What is the ratio of their perimeters and the ratio of their areas?


perimeter: 1:5 area: 1:25

perimeter: 1:5 area: 1:10

perimeter: 10:1 area: 5:1

perimeter: 25:1 area: 5:1

Answer 1

@ivettef365

Answer 2

perimeter will have the same ratio
area will have the square of the original ratio

Answer 3

go with the first one

Answer 4

1 to 5 and 1 to 5^2 which is:

1 to 5 and 1 to 25 first answer

Answer 5

This comes from:

Perimeter of the first triangle = x + y + z

Perimeter of the second triangle = 5x + 5y + 5z = 5(x + y + z)

Ratio = (x + y + z) / 5(x + y + z) = 1/5

Answer 6

uw! @InsanelyChaotic

Answer 7

The second ratio of 1/25 comes from:

1st triangle: area = (1/2)(b)(h)

2nd triangle: area = (1/2)(5b)(5h) = 25[(1/2)(b)(h)]

Ratio = (1/2)(b)(h) / 25[(1/2)(b)(h)] = 1/25