Question

I keep believing the answer is either 18,000 or 1,800 but im incorrect. Can someone please help me?? I use the formula A^2 *2*A*L=SA

Answer 1

SA = 280 cm²

Explanation:

SA = area of base + area of 4 congruent triangles

= 10² + (4 ×
`(1)/(2)` × 10 × 9 )

= 100 + (2 × 10 × 9)

= 100 + 180

= 280 cm²

Answer 2

The base is a square, so the area of the square is (10 cm)² = 100 cm²

To find the area of each triangle use the formula

base • height

10 cm • 9 cm = 90 cm²

now multiply by the number of triangles

90 cm • 4 = 360 cm²

Add the area of the square:

100 cm² + 360 cm² = 460 cm²

I hope it's correct