# How To: Find a slope of a line parallel/perpendicular to it

This video tells you how to find a slope of a parallel / perpendicular to it. In the equation y = mx + c, m is the slope. To calculate the slope of a line that is parallel to another line, you have to consider the rule m1 = m2 which means slope of the first line m1 is equal to the second line m2, if both the lines are parallel. Take the equation y = 2/3x - 7.2/3 is the slope. According to the rule m1 = 2/3 and so m2 = 2/3.Now to calculate the slope of perpendicular line you have another rule which says m2 = -1/m1.The slope of m2 is the negative reciprocal of m1.For example, take the equation y = -3/4 + 2.m1 = -3/4.Therefore m2 = + 4/3.Always right the rules as justification for full marks.

It’s Black Friday week on WonderHowTo! Don’t miss out on all of the big sales in the Gadget Hacks and Null Byte shops. And if you’ve been wanting to take some classes without going into debt, check out our best deals on online courses for a variety of skill sets. Don’t miss out on these huge discounts:

See Gadget Hacks’s top 10 BF sales on online courses (up to 99% off) >

See Null Byte’s top 13 BF sales on online courses (up to 99% off) >

• Hot
• Latest