 # Warm-up Find the area of the following: show calculations! 1.)2.) 3.) 4 inches 8 ft 12 cm 8ft 3 cm 3 inches.

## Presentation on theme: "Warm-up Find the area of the following: show calculations! 1.)2.) 3.) 4 inches 8 ft 12 cm 8ft 3 cm 3 inches."— Presentation transcript:

Warm-up Find the area of the following: show calculations! 1.)2.) 3.) 4 inches 8 ft 12 cm 8ft 3 cm 3 inches

Surface Area of Rectangular Prisms

A Rectangular Prism has 6 faces Bottom Top Left Right Front Back Length Height Width

A Rectangular Prism has 6 faces Left Top Back Front Bottom Right

In order to find the surface area, you find the area of each face, then add them all together. Left Length Back Front Bottom Right Height Width Height Length Width Height Top

In order to find the surface area, 2·(length·width) +2·(length·height) +2·(width·height) length width height 2LW+2LH+2WH = SA of Rectangular Prism

Let’s Practice!!

1) Find the surface area of the Rectangular Prism 12cm 10cm 8cm

1) Find the surface area of the Rectangular Prism 10cm 12cm 8cm Length = ? Width =? Height = ? 8 cm 12 cm 10 cm SA = 2·L·W + 2·L·H + 2·W·H =2·(8cm·12cm) + 2·(8cm·10cm) + 2·(12cm·10cm) =2·(96cm 2 ) + 2·(80cm 2 ) + 2·(120cm 2 ) =192cm 2 + 160cm 2 + 240cm 2 = 592 cm 2

2) Find the surface area of the Rectangular Prism 10m 5m 2m Length = Width = Height = 10m 2m 5m SA = 2·L·W + 2·L·H + 2·W·H =2·(10m·2m) + 2·(10m·5m) + 2·(2m·5m) =2·(20m 2 ) + 2·(50m 2 ) + 2·(10m 2 ) =40m 2 + 100m 2 + 20m 2 = 160m 2