<PRE><B>Question 466593</B>
M(3,5) and N(8,a) is 13


13= sqrt((3-8)^2+(5-a)^2)

13=sqrt(25+25-10a+a^2)
13=sqrt(50-10a+a^2)
square the equation
169 = a^2-10a+50
a^2-10a-119=0
Find the roots of the equation by quadratic formula							
							
a=	1	b=	-10	c=	-119		
							
b^2-4ac=	100	-	476				
b^2-4ac=	576		
{{{sqrt(576)}}}=	24
{{{x=(-b+-sqrt(b^2-4ac))/(2a)}}}							
{{{x1=(-b+sqrt(b^2-4ac))/(2a)}}}							
x1=(	10	+	24	)/	2		
x1=	17						
x2=(	10	-24	) /	2			
x2= 	-7						
a=17 OR -7</PRE>