Answer:
.
Step-by-step explanation:
X = ay
Hope this helps
Mark brainliest please
Answer:8pts
Step-by-step explanation:
Answer: 
Step-by-step explanation:
1. To write the number given in the problem (4,498,000,000) in scientific notation you must write it in the following form:

2. The decimal point must be written after the first digit and the exponent b must be positive and indicates the number of times the decimal point is move to the right. Therefore, you have:

D=dog's weight
c=cat's weight
d=7c
d+c=72
sub 7c for d
7c+c=72
8c=72
divide both sides by 8
c=9
d=7c
d=7(9)
d=63
dog=63lb