Question 547137
(r-2)(r+6)=11

r(r+6)-2(r+6)+11=0

r^2+6r-2r-12+11=0

r^2+4r-1=0
Find the roots of the equation by quadratic formula						
						
a=	1	,b=	4	,c=	-1	
						
b^2-4ac=	16	+	4			
b^2-4ac=	20					
{{{x=(-b+-sqrt(b^2-4ac))/(2a)}}}						
{{{x1=(-b+sqrt(b^2-4ac))/(2a)}}}						
{{{x1=(-12+21)/(2)}}}						
x1=(	-4	+	4.47	)/	2	
x1=	0.24					
x2=(	-4	-4.47	) /	2		
x2= 	-4.24	
you can also work it out in fractions