Question

Leonard made the 3-d shape below for an art project. He wants to paint it blue.

How many square centimeters of paint does he need to paint the outside of every
side except for the bottom?
10 cm
6 cm

Answer 1

90
`cm^(2)` of blue paint

Explanation:

From the given diagram, the sides have the same dimensions and the shape of a triangle.

Area of a triangle =
`(1)/(2)` x base x height

Given that, the base of each side = 6 cm, and the height = 10 cm.

Then,

Area of each side of the shape =
`(1)/(2)` x 6 x 10

= 30
`cm^(2)`

Since Leonard wish to paint only the 3 sides and not the bottom part of the shape, the amount of paint required can be determined as;

3 x area of each side = 3 x 30

= 90
`cm^(2)`

Leonard would need 90
`cm^(2)` of paint to paint the sides of the shape.