Since there is no value for either X or Y given, you can only change the formula around to equal X.
y=45x+38
First move the 38 to the left side by canceling it out (subtract 38 from both sides).
y-38=45x+38-38
So now we have:
y-38=45x
Now isolate the x on the right side by dividing both sides by 45.
(y-38) / 45 = x
So,
x = (y-38) / 45
(If the answer you’re looking for is a specific number, then the value for X or Y needs to be given!)
I know there must be an equation to do this, but there is a simpler way.
Just factor number 72 into two numbers which, when multiplied, equal 72. Two of such numbers are 9 and 8, and you can see that the difference between those two numbers is just 1. So that is the answer to your question - the length of the patio is 9 feet, whereas the width is 8 feet.
I just added the two numbers and got the number 100.88