Parallel and perpendicular lines
Linear functions and graphs · Stage 2
Recognize the pattern
Perpendicular nonvertical slopes are negative reciprocals.
Useful rulem₁=m₂; m₁m₂=-1
Build on: ALG-05
Try it before reading the solution
What slope is perpendicular to a line of slope 2?
This teaching example is original and is not an official SAT question.
Reasoning
The product of the two slopes must be −1; 2(−1/2) = −1.
Answer−1/2
03 · Next step
See membership →Ready for adaptive practice
Practice questions remain in English, as on the SAT.