In general, how does the growth of y=4x compare to the growth of y=4x

Select the number of ways in which a line and a circle can intersect

In the diagram, gef and hef are congruent. what is the value of x

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?