Answer:

Explanation:
As a first step to go into this problem, we need to make a diagram:
Let x be the measure of the longer leg.
Now, understanding this we can apply the Pythagorean theorem to find x, it is represented by the following equation:

Substituting a,b, and c by the expressions corresponding to its sides:

apply square binomials to expand and gather like terms, we get:

Now, factor the quadratic equation into the form (x+?)(x+?):

This means, the longer leg could be 4 or 12, but if we subtract 7 to 4, we get a negative measure for the shorter leg, that makes no sense.
Therefore, the long leg is 12 cm.
Hence, if the shorter leg is 7 centimeters shorter than the longer leg:
