Substitution
x-y=1
3x=3y+3

Two cyclists 84 miles apart start riding toward each other at the same. one cycles 2 times as fast as the other. if they meet 4 hours later, what is the speed (in mi/h) of the faster cyclist?

Write an algebraic expression to match each statement a. four less than 8 times a number b. twice the difference of a number and six c. nine from a number squared

What happens to the area as the sliders are adjusted? what do you think the formula for the area of a triangle is divided by 2?