Question

Use DESMOS: What is the equation

that represents a line that is
perpendicular to the graphed line and
passes through the point (-6, 6)?

Answer 1

y=mx+c

I picked the points (0, -4) and (-2,-10) to find the gradient of the line

M= rise/run

= 6/2

=3

Y-intercept is at - 4

Y= 3x - 4 is equation of the line given

Reciprocal of 3 is 1/3

(m1 x m2 = - 1)

So, to make - 1, our second gradient should be negative.

Gradient of the perpendicular line will be - 1/3

Y= - 1/3x + c

Substitute value of x & y into the equation

(-6,6) means x = - 6, y = 6

y = - 1/3x +c

6 = - 1/3 x - 6 + c

6 = 2 + c

-2

4 = c

Thus, final equation we're after will be:

y= - 1/3x + 4

Hope this helps!