The surface area of a rectangular prism is 150 cm². If all the sides are tripled, what will the new surface area be?

SA=2 (LW+LH+WH)

if all are trippled then

SA=2 (3L3W+3L3H+3W3H)

SA=2 (9LW+9LH+9WH)

SA=2 (9) (LW+WH+WH)

SA=9 (2 (LW+WH+WH))

the SA will be multiplied by 9

150 times 9=1350

new surface area is$1350 cm²