Pythagorean theorem and similarity, values of ad & ab? ( please round answer to nearest 10) work needed! please thanks.

9/10 divide by -3/15 as a mixed number

Find the area of the triangle formed by the origin and the points of intersection of parabolas y=−3x^2+20 and y=x^2−16.

Onnie is considering doing some long term investing with money that she inherited. she would like to have $50,000 at the end of 30 years. approximately how much money would lonnie need to put into an account earning 6% interest compounded annually in order to meet her goal?