lucky bee

y= X^2 + X - 500/10 and y is the number of milliliters of fuel consumed per second and X is the speed of the engine in revolutions per minute. If the engine operates between 100 revolutions per minute and 400 revolutions per minute what is the domain and...

Each of the three circles have a radius of 10. The line OA contains the center of the three circles, and the line OB is tangent to the right-hand circle. Find the length of segment CD