Ms+Dickson's+Class

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= = How To"... = Group 1: Find the height of the triangle (length of the altitude) given 3 points. You may use the triangle A(-1,3), B(-2, -1), and C(2, 1) to demonstrate the concept with altitude going from point A.



This is the triangle we will be using for our example. The co-ordiantes are as follows: A(-1,3), B(-2,-1), and C(2,1)



First you need to calculate the slope of line BC.



The slope of line AD is the negative reciprocal of line BC. Use the slopes to create a formula in y=mx+b form. Substitute the points in to get the y-intercept. Use substitution to find the point of intersection (POI) of the two lines to get the co-ordinates of D. Substitute the co-ordiates of D and A in to the formula for length. Formula for length=sqrt( (x1-x2) squared + (y1+y2) squared = THE MATH!!! = )