Let's call the lengths of our two types of sides <em />
and 
.
The two sides will that our 1.3 inches bigger than the third side will be have length x, and the length of the other side will be known as y. Thus,
.
Considering this, we can add our sides together and set this value equal to 8, given the information in the problem:
Now, let's solve for y.
Now, we are not done yet. We must determine the true lengths of all of our sides. Using the equation we found earlier, the length of the two bigger sides is
inches and the length of our smaller side is simply 
inches.
To verify, we can add these sides together and check that they equal 8:
3.1 + 3.1 + 1.8 = 8 ✔
The two sides will that our 1.3 inches bigger than the third side will be have length x, and the length of the other side will be known as y. Thus,
Considering this, we can add our sides together and set this value equal to 8, given the information in the problem:
Now, let's solve for y.
Now, we are not done yet. We must determine the true lengths of all of our sides. Using the equation we found earlier, the length of the two bigger sides is
To verify, we can add these sides together and check that they equal 8:
3.1 + 3.1 + 1.8 = 8 ✔