AlgebraEasyFinding x from a two-variable equation
Algebra practice question
For the equation x − 4y = 8, what is the value of x when y = −1?
Answer: 4
x − 4(−1) = x + 4 = 8, so x = 4.
Common wrong answers
- If you answered 8
- 8 ignores the y term.
- If you answered 12
- 12 treats −4(−1) as −4 and adds 4 to 8.
- If you answered -4
- −4 has the sign wrong.
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