Which transformation will preserve distance between points when applied to a figure in the (x, y)-coordinate plane

Which addition property is being illustrated below? (type commutative or associative) (6 + 7) + 1 = 6 + (7 + 1)

For what values of x is x2 + 2x = 24 true?

Stephen thublin invests $1,000,000 in a 45-day certificate of deposit with 6.55% interest. what is the total interest income from the investment?