Answer:
A
Step-by-step explanation:
Checking something is a way to see if your answer is reasonable.
Answer:
B:34
Step-by-step explanation:
16² + 30² = c²
256 + 900= 1156
square root of 1156 is 34
First, add 20 and 40. that gives you 60. then, you divide- 420/60. that gives you 7. then multiply 7 by 20, giving you 140, and multiply 7 by 40, giving you 280. then subtract: 280-140
answer: 140
