Question

What is the slope of the line perpendicular to `y=-3/7x+4`?

Answer 1

`slope = 7/3`

Explanation:

If 2 lines are perpendicular to each other then the product of their gradients is -1 .

let the gradients of the 2 lines be `m_1 color(black)(" and ") m_2`

then `m_1 xx m_2 = -1 ............(*)`

the equation `y = -3/7 x + 4`
is of the form y = mx + c where m represents the gradient and c , the y-intercept.

so `m_1 = -3/7 color(black)(" and require to find ") m_2`

using equation (*) : `-3/7 xx m_2 = -1 color(black)(" then ") m_2 =-1/(-3/7)`

slope of perpendicular is `-1 xx -7/3 = 7/3`