Question

area of rectangle
a = l · w
which expression can be used to find
the surface area of the prism?
(20·8) + (20·3) + (8·3)
2(20·8) + 2(20·3) + 2(8·3)
2(20·8·3)
20·8·3
(image with dimensions: 20 cm, 8 cm, 3 cm for the prism net)

Explanation:

Step1: Recall surface area formula for prism

A rectangular prism has 6 faces: 2 of each pair of dimensions. Surface area = sum of all faces' areas.

Step2: Calculate each face area

Areas of face pairs: $2(20×8)$, $2(20×3)$, $2(8×3)$. Sum them.

Step3: Match with options

The sum $2(20×8)+2(20×3)+2(8×3)$ is the correct expression.

Answer:

2(20·8) + 2(20·3) + 2(8·3)