Question

hellltp

Answer 1

the three problems basically follow the same logic, so I'll walk you through the first problem and let you try problems 2 and 3 on your own.

a) the temperature was 80 F and then fell 20 F.

because the temperature starts at 80, logically the arrow must start also start at 80. Because the temperature fell 20 degrees, then the arrow must be 20 degrees long to represent the change.

for the addition sentence, you'd start with 80 on the left. because the temperature is decreasing by 20, you'd add -20 to represent a decrease of 20.