Educator

Solving by Substitution

• To find exact solutions, use algebraic methods like the substitution method.

• Use substitution when at least one of the coefficients in the system is 1 or –1. Solve for this variable in terms of the other one. Then substitute that expression into the other equation.

• If you eventually get an equation that is always true, then the system has an infinite number of solutions.

• If you eventually get an equation that is never true, then the system has no solution.