Question

Please answer before Monday 9 a.m.I have to go to school that day at that time.

Answer 1

Answer:

• First choice, 984 cm²

Explanation:

The plastic pencil case has form of a triangular prism.

This triangular prism has five faces:

• Top and bottom faces: two congruent triangles with a 10 cm base and 12 cm height.

• Lateral faces: two congruent rectangles with a 24 cm length and 13 cm widht, and one rectangle with 24 cm length and 10 cm widht.

Surface area:

• Top and bottom triangles:

        area = (1/2) base × height

         area of one triangle = 10 cm × 12 cm × (1/2) = 60 cm²

          area of the two triangles = 2 × 60 cm² = 120 cm²

• Lateral rectangles:

        area of a rectangle = length × width

         area of the trhee triangles = 24 cm × 10 cm + 2 × 24 cm × 13 cm = 240 cm² + 624 cm² = 864 cm².

• Total area: 120 cm² + 864 cm² = 984 cm²

Answer: first choice, 984 cm²