Checkpoint: clothes, methods, endings and graphs

Which equation is the same line as 2x − 4y = 6?

• `x − 2y = 3`
• `x + 2y = 3`
• `x − 2y = 6`

Take y = 2x + 1 and 3x + y = 11. Which method can start at once, with no rearranging?

• Substitution, because y stands alone
• Neither, because the pair has no answer
• Elimination, because the x-terms match

Elimination ends on 0 = 0. What is true?

• The answer is 0.
• No point works.
• Every point of the line works.

A pair gives x = 3.5 for the number of buses. What is wrong?

• The equations were copied wrongly.
• A number of buses must be whole.
• Nothing is wrong.

Two lines on a graph cross at (4, 1). What is the solution of the pair?

• Infinitely many solutions
• x = 1 and y = 4
• x = 4 and y = 1