List all the factors of 15. tell whether 15 is prime or composite.

x+y=90

x=30-y=x

step-by-step explanation:

if you understand you will get the answer

38.5

step-by-step explanation:

lets say, first number = r

second number = 3r+7

total = 49

(r)+(3r+7)= 49

4r+7 = 49

4r = 42

r = 42/4

r= 10.5

3r+7 = 3(10.5)+7 = 38.5

hope this