16Hit1600
AlgebraEasy–MediumThird point on a line

Algebra practice question

The points (1, 5), (3, 11), and (5, k) lie on the same line in the xy-plane. What is the value of k?

Answer: 17

The slope from (1, 5) to (3, 11) is 3, so from x = 3 to x = 5 the y-value rises by 6, from 11 to 17.

Common wrong answers

If you answered 13
13 adds 2 to 11, the change in x.
If you answered 14
14 adds 3 once instead of twice.
If you answered 16
16 treats the rise from 5 to 11 as continuing by 5.

More Algebra questions

Not affiliated with the College Board. SAT is a trademark of the College Board.