Answer:
w=7 5/8
l = 29.875
Explanation:
We have to use system of equations here
Let l be length and w be width
l = 3w+7
w=l(1/3)-7
We can use the equation:
l+w+l+w = 75
2l+2w = 75
Now we substitute l for what we said above
2(3w+7)+2w=75
6w+14+2w=75
Combine like terms
8w+14=75
Subtract 14 on both sides
8w=61
w=7 5/8
We can use what we know about the relationship of the width and the length to find the length
7 5/8 * 3 + 7 = 29.875
l = 29.875