Determine whether y varies directly with x. if so, find the constant of variation k and write the equation.
x y
7 11
8 13
9 15
10 17

In triangle abc segment de is parallel to the side ac . (the endpoints of segment de lie on the sides ab and bc respectively). find de, if ac=20cm, ab=17cm, and bd=11.9cm;

Acertain population of bacteria demonstrates exponential growth doubles in size every 4 days. how long will it take the population to triple in size?

Someone answer asap for ! a ball is rolled down a ramp. the height, f(x), in meters, of the ball x seconds after it is released is modeled by the function f(x) = x²- 10x + 25 for all values of x from 0 to 5. which statement about the ball is true? a. the maximum height of the ball is 5 meters b. the height of the ball increases from 0 to 5 meters above the ground. c. the ball has traveled 5 meters when it reaches the bottom of the ramp. d. the ball has been traveling for 5 seconds when it reaches the bottom of the ramp