Simplify: (3x2 + 4x - 3) - (4x2 - 3x + 2)

Which expression is equivalent to -5(3x - 6/7)

15 and 14.7 are 1 apart, so 15 – 14.7 must be 1.

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?