If 3x=21, what is 9x? To get the answer, solve the equation for the variable. Then plug that variable value into the expression and simplify to get the answer. Follow this same process anytime you need to use an equation to evaluate an expression. Watch this tutorial to see this process in action!
Plugging variables into an expression is essential for solving many algebra problems. See how to plug in variable values by watching this tutorial.
You can't do algebra without working with variables, but variables can be confusing. If you've ever wondered what variables are, then this tutorial is for you!
Solving an equation for a variable? Perform the order of operations in reverse! Check it out in this tutorial.
Solving an equation for a variable? Perform the order of operations in reverse! Check it out in this tutorial.
Word problems are a great way to see math in action! See how to translate a word problem into an equation, solve to find the answer, and check your found answer all in this tutorial.
Trying to solve two equations each with the same two unknown variables? Take one of the equations and solve it for one of the variables. Then plug that into the other equation and solve for the variable. Plug that value into either equation to get the value for the other variable. This tutorial will take you through this process of substitution step-by-step!