What are the coordinates of the y-intercept for y=ax^2+bx+c

Average salary for a medical assistant is $31,220 which is a 20% income tax bracket how much money would they pay in income tax?

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

Suppose that one doll house uses the 1 inch scale, meaning that 1 inch on the doll house corresponds to 1/2 foot for life-sized objects. if the doll house is 108 inches wide, what is the width of the full-sized house that it's modeled after? in inches and feet.