Answer:
The answer is "
"
Step-by-step explanation:
Given values:

Using formula:

Put the values in the above formula:

Answer:
???
Step-by-step explanation:
The easy thing to do is eliminate x by subtraction
x + 7y = 24
- x - 9y = -24
-------------------
16y = 48
now solve for y and then substitute the value into either original equation to find x
in order to know the greatest common multiple of 84 you would have to compare it to another number