Help me please! is compound interest

Mary beth used the mapping rule to find the coordinates of a point that had been rotated 90° counterclockwise around the origin. examine the steps to determine whether she made an error. m (3, –6) is rotated 90° counterclockwise. (x, y) → (–y, x) 1. switch the x- and y-coordinates: (6, –3) 2. multiply the new x-coordinate by –1: (6(–1), –3) 3. simplify: (–6, –3) .

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)

Prove that quadrilateral is a rhombus.