S samsonhohoho New Member Joined Feb 19, 2012 Messages 17 Gender Male HSC 2013 Nov 23, 2012 #1 One root of the equation x^2 - (r+3)x + 2(r+1) = 0 is twice the other root. Find the two possible values of r. Please show working THANKS!
One root of the equation x^2 - (r+3)x + 2(r+1) = 0 is twice the other root. Find the two possible values of r. Please show working THANKS!
nightweaver066 Well-Known Member Joined Jul 7, 2010 Messages 1,585 Gender Male HSC 2012 Nov 23, 2012 #2 Let the roots be a and 2a. Sum of roots = 3a = r + 3 Product of roots = 2a^2 = 2(r + 1) a^2 = r + 1 Simultaneous equations to get possible values of r.
Let the roots be a and 2a. Sum of roots = 3a = r + 3 Product of roots = 2a^2 = 2(r + 1) a^2 = r + 1 Simultaneous equations to get possible values of r.