Quadratics with equal roots.
I think this is the right place to post this, I'm in England and don't know how the American schooling system works, but here goes:
"Find the values of k for which kx(sq)+8x+k = o has equal roots."
I know that for this equation to have equal roots the discriminant must equal zero, so:
b(sq)-4ac = 0
Putting numbers into this I get:
64-4k(sq) = 0
This is where i get stuck - do I first square root each side, giving:
and getting an answer 2, or do I first divide each side by 4, giving:
and getting 4 as the answer?
So to sum up, do I square root first, or simplify first?
Thanks in advance.