2 pre-calc problems! I'm trying to set it to 20 so sorry if its less

Triangle abc has side lengths: ab = 3.5  cm, bc = 2.4 cm, and ac = 4.2 cmδabc ≅ δhjkwhat is the length of side hj?

Shelly bought a house five years ago for $150,000 and obtained an 80% loan. now the home is worth $140,000 and her loan balance has been reduced by $12,000. what is shelly's current equity?

The number 72 lies between what perfect squares