WAEC - Mathematics (2005 - No. 25)
Given that the root of an the equation \(2x^2 + (k+2)x+k=0\) is 2, find the value of k
-4
-2
-1
\(-\frac{1}{4}\)
Објашњење
Substituting for x in the equation
\(2(2)^2 + (k+2)2+k = 0 \Rightarrow 8 +2k + 4 + k =0 \Rightarrow 3k =-12; k=-4\)
\(2(2)^2 + (k+2)2+k = 0 \Rightarrow 8 +2k + 4 + k =0 \Rightarrow 3k =-12; k=-4\)