## nexis 3 years ago In 4a) http://ocw.mit.edu/courses/mathematics/18-01sc-single-variable-calculus-fall-2010/exam-3/materials-for-exam-3/MIT18_01SCF10_exam3sol.pdf How do we find the formula for hypotenuse of the triangle? (h-hx/r) (Just for x) (Sorry, somehow this question got closed before)

1. Coolsector

you ask how they got y = h- hx/r ?

2. nexis

yes

3. tjones89

4. Coolsector

we have two points : ( 0,h) and (r,0)

5. Coolsector

hence the slope : (h-0) /(0-r) = -h/r and using y = y1 + m(x-x1) we get : y = h -hx/r

6. nexis

sorry, why are we using h for y1?

7. nexis

i can see how we get the slope

8. Coolsector

we can take one of the points : (0,h) or (r,0) to be (x1,y1) in both cases we will get the same answer

9. Coolsector

lets take the (r,0) so y1 = 0 : y = 0 + -h/r(x-r) y = h -hx/r

10. nexis

indeed O_O

11. Coolsector

we find slope then we can choose any given point on the line to construct our line equation :)

12. nexis

yes

13. nexis

great, got it, thanks :)

14. Coolsector

yw