1. Which of the following expressions is 5 times as much as the sum of r and s? *
A. 5 × r + s
B. 5 + r + s
C. r + s × 5
D. (r + s) × 5

Answer is D

Step-by-step explanation:

you want to multiply 5 to r and s so then r and s. so the forth one would be distributed into both r and s.

5x+40

5(x + 8)

7x - 49

7(x - 7)

18x + 9

9(2x + 1)

15x - 10

5(3x - 2)

step-by-step explanation:

for number one all you have to do is factor 5 out of 5x + 40

for number 2 factor 7 out of 7x - 49

for number three factor 9 out of 18x + 9

for number four factor 5 out of 15x - 10

it is true

step-by-step explanation:

all the combinations add up i used   calculator