Question

X squared-(k+3)x+4k=0
Please help me find the value of k for which there are equal roots but of opposite sign
Working out please thanks

Answer 1

Let r be the root:
x²-(k+3)x+4k= 0 = (x-r)(x+r)=x²-r²
equating coefficients,
-(k+3)=0, k=-3
4k=-r², r=sqrt(3*4)=2√3
or the equation is
x²-12=0
Find k from the equation.