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One, zero, and infinite solutions
Not all linear equations in one variable have exactly one solution. Some have no solutions, others have exactly one, and then still others may have an infinite number of solutions.
Sal shows how some equations have one solution (like -7x + 3 = 2x + 2) and others have no solutions (like -7x + 3 = 2x + 2 - 9x) and still others have infinite solutions (like -7x + 2 = 2x + 2 - 9x).
An equations with NO solution? Is that possible? In this video, Sal attempts to solve 8(3x + 10) = 28x - 14 - 4x only to find that there isn't a solution.
Sal shows how to complete the equation -11x + 4 = __x + __ so that it has no solutions.
Sal shows how to complete the equation 4(x - 2) + x = 5x + __ so that it has infinitely many solutions.
Practice telling whether an equation has one, zero, or infinite solutions.