Give the slope of a line perpendicular to the given line. (how do you do it) y=3x+5

I believe it is -1/3 for the slope. Because i searched for an example and this is what it gave me.

Because the slope need to be reciprocal of each other. So for instance the equation of the line perpendicular to the line whose equation is 2y-4x = 7 the slope of this line is 2. therefore the reciprocal is -1/2 or -0.05

For your problem to check plot the points to your equation then use the point intercept form which is:

y - y1 = m(x -x 1)

then get a point on your line and use the (x,y) plug it in using your new slope and you will end up with a second equation that shows your slope. And you will see from the diagram that they are perpendicualr. I hope this helps you. You can also practice more going to the search engine and typing in parallel and perpendicular lines and see all examples.