Please help me with this math. find x and y

Give all possible names for the line shown. calculation tip: lines can be written with either point first.

Aplot of land has been surveyed for a new housing development with borders ab, bc, dc, and da. the plot of land is a right trapezoid with a height of 60 feet and an opposite leg length of 65 feet

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25