Question

Which one of these equations has one solution, and which has no solutions? (Math)

Answer 1

One solution means that x will only equal one number.

Many solutions means that no matter what number you replace x with, the equation will still be true.

No solution means that no matter what number you replace x with, the equation will be false, as both sides will not match.

One solution: x - 2 = 12

Check: Isolate the variable, x. Add 2 to both sides. Note the equal sign, what you do to one side, you do to the other:

x - 2 (+2) = 12 (+2)

x = 12 + 2

x = 14

Many solution: x + 3 = 3 + x

Check: Plug in numbers for x. If no matter what number you plug in, the equation is true, there is infinite amount of solutions:

If x = 1:

1 + 3 = 3 + 1

4 = 4

If x = 2:

2 + 3 = 3 + 2

5 = 5

etc.

No solution: x - 1 = x + 5

Check: No matter what number you plug in for x, both sides of the equation will not match. Check:

If x = 1:

1 - 1 = 1 + 5

0 ≠ 6

If x = 2:

1 - 2 = 2 + 5

-1 ≠ 7

etc.

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