Posted by jennifer on .
boating
The inclined ramp of a boat launch is 8 meters longer than the rise of the ramp.
The run is 7 meters longer than the rise. How long are the three sides of the ramp?
please explain how to do this one

MATH 
Reiny,
the the rise be x m
then the run is x+7 m , and the ramp (the hypotenuse) is x+8 m
then
x^2 + (x+7)^2 = (x+8)^2
expand and simplify to
x^2  2x  15=0
Can you take it from there?
(it factors) 
MATH 
jennifer,
is this right
x^2 2x15=0
x^21x1x15=0
1x(1x+1) 1(1x+1)
is this right? 
MATH 
Reiny,
no
x^2  2x  15=0
(x5)(x+3)=0
x = 5 or x =3
clearly x has to be positive
so the height of the ramp is 5, take it from there. 
MATH 
jennifer,
ok
so if the height is 5 then other side would be
13m and 12m?