Sam used 4/5 of his gas in his car. if his car’s gas tank started with 20 gallons, how many gallons did sam use?

16 Gallons

Step-by-step explanation:

4/5*4=16/20

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