Angles Between LinesBy the end of the day you should be able to…•Find the angle of inclination of a line•Find the angle between two lines

TS: Explicitly assessing information & drawing conclusions

Warm Up:What was the formula for tan(x – y) again?(You have notes & I have books so you should be able to find it somewhere if it’s not still engrained in the brain.)

Angle of Inclination

x

y

Example:1) Find the angle of inclination for the line 2x – y + 3 = 0

2) Find the equation of the line with a y-intercept of 3 and an angle of inclination of 3π/4

Angle Between Two Lines

x

y

Example:

Find the acute angle formed by the lines 2x + 3y = 4 and x – 4y + 3 = 0

Finding the angles of the triangle

(-1, -5)

(4, 3)

(2, 3)