The equation of line n is 8x - 14y + 3 = 0.

What is k if the graphs of n and kx - 7y + 10 = 0 are perpendicular?

For perpendicular lines:

"Their slopes' product is - 1"

As these lines should be parallel, so their slopes would be the same.

Slope of line n:

8/14 = 4/7

Slope of the other line:

k/7

Equating them:

4/7 * k/7 = - 1

4k / 49 = - 1

4k = - 49

k = - 49/4 = - 12.25

This means k = - 12.25

Sorry for confusion