A triangle has corners A, B, and C located at (2,2), (3,4), and (6,8), respectively. What are the endpoints and length of the altitude going through corner C?

1 Answer
Jan 30, 2017

The endpoints of altitude through corner C are:C(6,8) and D(5.2,8.4)

The length of altitude is : 0.89

Explanation:

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The slope of line through A(2,2) and B(3,4) is :

m=4231=21=2

now,let us find the slope of line passing C(6,8) and D(x,y)

if two line is perpendicular , product of their slopes is equal to -1

mn=1
2n=1
n=12

now ,let us write equations of lines

equation for line passing A(2,2) and D(x,y)
y2=2(x2)
y=2x4+2
y=2x2 (1)

equation for line passing C(6,8) and D(x,y)
y8=12(x6)
y=12(x6)+8

y=12x+3+8

y=12x+11 (2)

let us write the equations (1) and (2) as equal

2x2=12x+11

2x+12x=11+2

52x=13 , 5x=132 ,x=265 , x=5.2

use equation (1) or (2)

y=2x2

insert x=5.2

y=25.22
y=10.42
y=8.4

D=(5.2,8.4)

the end points are C(6,8) and D(5.2,8.4)

The length of the altitude can be calculated using :

hC=(5.26)2+(8.48)2

hC=(0.8)+(0.4)2

hC=0.64+0.16

hC=0.80

hC=0.89