Angle Inclination of a Line - Problem 1


Let's do a problem that involves the angle of inclination of a line. Line L passes through point -1,3 and makes an angle of 70 percent on the x axis, this is its angle of inclination, find its slope to the nearest hundredth.

Well slope m equals the tangent of the angle of inclination so in this case the tangent of 70 degrees. And I’m asked to find that to the nearest hundredth so I'll need a calculator. So I hit tangent of 70 and I get to the nearest hundredth 2.75. So approximately 2.75 and that’s going to be my slope. Find an equation for line L, well since I have a point that it passes through in the slope I could use point slope. So y minus 3 equals 2.75 x minus -1 x plus 1. That would be an equation for line L.

angle inclination horizontal lines tangent slope