Question 539689
height at which the ladder touches the wall								=	15		ft	
												
Distance from foot of the ladder to the wall=	x				
												
Length of the ladder =	2	x	+	1				
												
The ladder,the floor & the wall form a right triangle.												
The base is one leg	.The height is the other leg							
The ladder acts as the hypotenuse												
Pythagoras theorem												
												
(Hyp)^2= 		(leg1)^2+			Leg2^2							
(2x+1)^2	=	X^2	+	15	^2		
X^2+4x	+	1	=X^2+225			
												
4X^2-	x^2	+	4	x+	1		-225			
												
3	X^2-	+	4	x  		-224						
												
Find the roots of the equation by quadratic formula												
												
a=	3	,b=	4	,c=	-224							
												
b^2-4ac=	16	+	2688									
b^2-4ac=	2704											
{{{x=(-b+-sqrt(b^2-4ac))/(2a)}}}												
{{{x1=(-b+sqrt(b^2-4ac))/(2a)}}}												
{{{x1=(-12+21)/(12)}}}												
x1=(	-4	+	52	)/	6							
x1=	8	ft										
x2=(	-4	-52	) /	6								
x2= 	-9.33											
Ignore negative value												
height at which the ladder touches the wall	=	8	ft									
												
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