Tidy, Then Solve
Part of the Fundamentals section of Coddy's Math journey. Lesson 27 of 64.
Longer equations are the same equations with more tidying in front. 2(x + 1) + 3x = 17: distribute first, then collect, then undo.
2x + 2 + 3x = 17
5x + 2 = 17
5x = 15
x = 3
That is the whole routine for one side: distribute, collect, undo. Nothing here is new; it is the last four lessons in a row. When an equation looks long, do not look for a clever trick. Look for a bracket to open or a pair of like terms to merge, and the equation shortens itself.
Challenge
Solve the equation 3(x + 2) + 2x = 21 for x.
Try it yourself
Solve for x
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Fundamentals
1What an Equation Is
The EquationFinding the UnknownThe Same to Both SidesSolved Means AloneRecap: First Equations4Two-Step Equations
Two Layers to UndoSubtract, Then DivideAdd, Then DivideA Division InsideNegatives in Two StepsRecap: Two-Step Equations2One-Step Equations
Undoing AdditionUndoing SubtractionUndoing MultiplicationUndoing DivisionInverse OperationsRecap: One-Step Equations5Tidying First
Like TermsTerms and Numbers MixedThe Distributive PropertyDistributing a SubtractionTidy, Then SolveRecap: Tidying First