Luis and Roberto are donating some of their baseball cards to the library. Luis started with 50 cards and gave away X number of them. Roberto started with 80 cards and gave away 3 times as many as Luis had given away. If they both now have the same number of baseball cards, how many baseball cards did Roberto give away? A - 15
B - 35
C - 45
D - 65

the answer is c -45

explanation

calculator and a brain

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 has changed from the width and the height.

step-by-step explanation: