A substance’s decay function is represented by the equation y=10(0.87)x, where x is in hours. How long will it take until only 2.5 units of the substance is left? Justify your reasoning. Answer in complete sentences.

Use set builder notation to represent the following set: { -3, -2, -1, 0}

What is the value of x in the diagram below?

The general form of the quetion of a circle is ax^2+by^2+cx+dy+e=0 where a=b=0 if the circle has a radius of three units and the center lies on the y axis which set of values of a, b, c, d, and e might correspond to the circle