You cannot simplify 30/q anymore
If you want x, rearrange <span>Z=y+mx as follows: mx = z - y. Then div. all 3 terms by m:
z-y
x = ------- (answer).
m </span>
First convert everything into inches.
1 foot = 12 in
5 feet = 5*12 = 60 in
12 feet = 12*12 = 144 in
Now add them together
60 + 9 + 144 + 3 = 216 in
or
18 feet
Hope this helps :)