The equation of a line is 5x - 2y = 10. What is the slope of a line perpendicular to this line?
Show answer & explanation
Correct answer: B
Explanation
Line: 5x − 2y = 10
Slope of the line (m) = −a/b [ax + by + c = 0]
The product of the slopes of perpendicular lines = −1
5x − 2y = 10
2y = 5x − 10
y = (5/2)x − 5
Therefore, slope m₁ = 5/2
Slope of the perpendicular line = m₂
m₁ × m₂ = −1
(5/2) × m₂ = −1
m₂ = −2/5