A substance decays so that the amount A of the substance left at time t is given by: A = A0 ∙ (0.8)t where A0 is the original amount of the substance. What is the half-life (the amount of time that it takes to decay to half the original amount) of this substance rounded to the nearest tenth of a year? 3.1 0.6 2.5 1.6

What is the value of x? enter your answer in the box. x = two intersecting tangents that form an angle of x degrees and an angle of 134 degrees.

The equation of a circle is (x + 4)2 + (y + 6)2 = 16. determine the length of the radius. 10 4 16 8 my flower basket delivers flowers within a 20 mile radius of their store. if this area is represented graphically, with my flower basket located at (5, 2), what is the equation that represents the delivery area? (x - 2)2 + (y - 5)2 = 20 (x - 5)2 + (y - 2)2 = 20 (x + 5)2 + (y + 2)2 = 400 (x - 5)2 + (y - 2)2 = 400

Lindsay used two points, (x,y; ) and (+2.82), to find the equation of the line, y = mx + b, that passes through the points. y2-y, first, she used the definition of slope and determined that the value of mis x, - . given this information, which expression must represent the value of b?