Which expressions would complete this equation so that it has infinitely many solutions? 8+2(8x – 6 ) = choose exactly two answers that are correct.
a. 2(4x+7)
b. 9x – 10
c. 16x – 4
d. 4(4x – 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?