Question

write the slope-intercept equation for the line that passes through (-7,6) and is perpendicular to -7x+9y=-2

Answer 1

Using the formula of the line -7x+9y=-2
Rearrange it to,
9y= 7x-2
y= 7/9 x - 2/9

The gradient of this line is 7/9

The gradient perpendicular to this will be -9/7

Substitute (-7,6) and gradient=-9/7 to formula for a line y=mx+c
6= (-9/7)(-7) + c
c = -3

Thus the equation of the line is,
y=(-9/7)x -3