Solve for x in a Right Triangle

In a right triangle, the lengths of the two legs are given as $x$ and $x + 4$ units. If the hypotenuse of the triangle is $10$ units, calculate the value of $x$.

Recall that in a right triangle, the Pythagorean theorem states that the square of the length of the hypotenuse ($c$) is equal to the sum of the squares of the lengths of the other two sides ($a$ and $b$): $$ c^2 = a^2 + b^2 $$.