Pythagoras theory finding short and long sides

Task goals

• Identify the hypotenuse as the longest side, opposite the right angle, before writing $a^2+b^2=c^2$.
• Find a missing hypotenuse by adding the squares of the two shorter sides, then taking the square root.
• Find a missing shorter side by subtracting a known square from the hypotenuse's square, then taking the square root.
• Leave an answer as a simplified surd such as $\sqrt{19}$ when it is not a perfect square, unless asked to round.