Question

Area and perimeter of geometric functions

Answer 1

Answer: OPTION C

Explanation:

Calculate the height AD with Pythagorean Theorem:

`AD=\sqrt{20^(2)-16^(2)}=12`

Calculate the base CD with Pythagorean Theorem:

`CD=\sqrt{15^(2)-12^(2)}=9`

The perimeter is the sum of all the sides, therefore the perimeter is:

`P=9+15+16+20=60`

Answer 2

C. 60

Explanation:

From triangle ADB,

`|AD|^2+|BD|^2=|AB|^2`

`|AD|^2+16^2=20^2`

`|AD|^2=20^2-16^2`

`|AD|^2=400-256`

`|AD|^2=144`

`|AD|=√(144)`

`|AD|=12`

From triangle ADC,

`|CD|^2+12^2=15^2`

`|CD|^2+144=225`

`|CD|^2=225-144`

`|CD|^2=81`

`|CD|=9`

The perimeter is the distance around the figure.

The perimeter

`=15+20+16+9`

`=60`