A Negative Answer
Part of the Fundamentals section of Coddy's Algebra journey. Lesson 13 of 64.
An equation can have a negative solution. In x + 5 = 2, a number plus 5 gives 2, so the number must be less than zero. Solve it the usual way. Subtract 5 from both sides:
x + 5 - 5 = 2 - 5
x = -3
Check the answer in the original equation: -3 + 5 = 2, which is true.
An equation can have a negative solution. Keep the sign you get from solving. Then substitute the answer into the original equation to check that both sides are equal.
Challenge
EasySolve the equation x + 8 = 3 for x.
Try it yourself
x + 8 = 3
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