Question

4. Write the equation of line that is perpendicular to y= -1/3x + 7 and has a y intercept of -1.

1

Answer 1

y = 3x - 1

Explanation:

Two lines are perpendicular if the product of theirs slopes is equal -1:

y=m₁x+b₁ ⊥ y=m₂x+b₂ ⇒ m₁×m₂ = -1

y = -1/3x + 7 ⇒ m₁=-1/3

-1/3×m₂ = -1 ⇒ m₂ = 3

The y-intercept is b=-1 so the equation in slope-intercept form:

y = 3x - 1