The hypotenuse of a right-angled triangle is 3 more than one of the legs, and the second leg is 6. Find the hypotenuse.

One leg of a right-angled triangle is 6 cm, the second is x-cm, the hypotenuse is x + 3 cm.Then, by the Pythagorean theorem, we obtain the equation:
(x + 3) ² = 6² + x².
Let’s expand the brackets:
x² + 2 * 3 * x + 9 = 36 + x².
Let’s group the equation:
x² + 6 * x-x² = 36-9.
6 * x = 27.
x = 27/6 = 4.5 cm, this is the second leg.
Let’s define the hypotenuse:
x + 3 = 4.5 + 3 = 7.5 cm.
Answer: The hypotenuse is 7.5 cm.