Answer:
1st pic : 3²+4²=5²
2nd pic: 9 in.
Explanation:
According to Pythagoras theorem , in a right angled triangle, where
the longest side (opposite to the right angle) say its length X , the other two sides say Y,Z.
X² = Y² + Z²
Y² = X² - Z²
Z² = X² - Y²