Lines are perpendicular when the slopes are exact opposites. (the sign and the number are opposites)
For example:
slope = -2
perpendicular line's slope = 1/2(positive)
slope = 4/5
perpendicular line's slope = -5/4(negative)
slope = -2/3
perpendicular line's slope = 3/2(positive)
24. Use the slope formula to find the slope of a and b, and plug in the points.
[tex]m = \frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]
slope of a:
[tex]m = \frac{5-2}{-1-3} = \frac{3}{-4}[/tex]
slope of b:
[tex]m = \frac{6-2}{3-0} = \frac{4}{3}[/tex]
These lines are perpendicular
25. isolate the "y" for both equations
equation a:
2x - 4y = -3 Subtract 2x on both sides
-4y = -3 - 2x Divide -4 on both sides
y = 3/4 + 1/2x
The slope is 1/2
equation b:
x + 2y = -6 Subtract x on both sides
2y = -6 - x Divide 2 on both sides
y = -3 - 1/2x
The slope is -1/2
These lines are NOT perpendicular
