Math  /  Geometry

QuestionFind the length of the altitude in ABC\triangle \mathrm{ABC} from B Given: A(0,2),B(3,7),C(5,3)\mathrm{A}(0,2), \mathrm{B}(3,7), \mathrm{C}(5,3) Extra Credit: Find the parametric vector equation and standard

Studdy Solution

STEP 1

1. We are given the coordinates of points A, B, and C.
2. We need to find the length of the altitude from point B to line AC.
3. The altitude is the perpendicular distance from point B to line AC.
4. We will find the equation of line AC and use it to find the perpendicular distance from B.

STEP 2

1. Find the equation of line AC.
2. Calculate the perpendicular distance from point B to line AC.
3. Extra Credit: Find the parametric vector equation and standard form of line AC.

STEP 3

To find the equation of line AC, we need the slope of line AC. The slope m m is given by:
m=y2y1x2x1 m = \frac{y_2 - y_1}{x_2 - x_1}
Using points A(0, 2) and C(5, 3):
m=3250=15 m = \frac{3 - 2}{5 - 0} = \frac{1}{5}

STEP 4

Using the point-slope form of a line yy1=m(xx1) y - y_1 = m(x - x_1) , we can write the equation of line AC. Using point A(0, 2):
y2=15(x0) y - 2 = \frac{1}{5}(x - 0) y=15x+2 y = \frac{1}{5}x + 2

STEP 5

To find the perpendicular distance from point B(3, 7) to line AC, use the formula for the distance from a point to a line Ax+By+C=0 Ax + By + C = 0 :
Distance=Ax1+By1+CA2+B2 \text{Distance} = \frac{|Ax_1 + By_1 + C|}{\sqrt{A^2 + B^2}}
Convert the line equation y=15x+2 y = \frac{1}{5}x + 2 to standard form:
y15x2=0 y - \frac{1}{5}x - 2 = 0 15x+y2=0 -\frac{1}{5}x + y - 2 = 0 1x5y+10=0 1x - 5y + 10 = 0
Here, A=1 A = 1 , B=5 B = -5 , C=10 C = 10 .

STEP 6

Substitute point B(3, 7) into the distance formula:
Distance=1(3)5(7)+1012+(5)2 \text{Distance} = \frac{|1(3) - 5(7) + 10|}{\sqrt{1^2 + (-5)^2}} =335+101+25 = \frac{|3 - 35 + 10|}{\sqrt{1 + 25}} =2226 = \frac{|-22|}{\sqrt{26}} =2226 = \frac{22}{\sqrt{26}}

STEP 7

Extra Credit: Find the parametric vector equation of line AC. The direction vector of AC is 50,32=5,1 \langle 5 - 0, 3 - 2 \rangle = \langle 5, 1 \rangle .
The parametric equations are:
x=0+5t x = 0 + 5t y=2+1t y = 2 + 1t

STEP 8

Extra Credit: Convert the line equation y=15x+2 y = \frac{1}{5}x + 2 to standard form:
y15x2=0 y - \frac{1}{5}x - 2 = 0 15x+y2=0 -\frac{1}{5}x + y - 2 = 0 1x5y+10=0 1x - 5y + 10 = 0
The length of the altitude from B to line AC is:
2226 \frac{22}{\sqrt{26}}
The parametric vector equation of line AC is:
x=5t x = 5t y=2+t y = 2 + t
The standard form of line AC is:
x5y+10=0 x - 5y + 10 = 0

Was this helpful?

Studdy solves anything!

banner

Start learning now

Download Studdy AI Tutor now. Learn with ease and get all help you need to be successful at school.

ParentsInfluencer programContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord