If a quadratic function is concave down, which of the following is true? a is positive
a is negative
a is zero

Two cyclists 84 miles apart start riding toward each other at the same. one cycles 2 times as fast as the other. if they meet 4 hours later, what is the speed (in mi/h) of the faster cyclist?

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6

Uestion 1(multiple choice worth 5 points) (05.02)alex wants to paint one side of his skateboard ramp with glow-in-the-dark paint, but he needs to know how much area he is painting. calculate the area of the isosceles trapezoid. isosceles trapezoid with top base 12 feet, bottom base of 18 feet, and height of 6 feet. 72 ft2 84 ft2 90 ft2 108 ft2