Question

For what values of k such that kx^2 -10x +5k=0, k NOT=0, will have 2 real roots?

Answer 1

you want the discriminant to be positive, so solve for \(k\)
\[100-4\times k\times 5k>0\]

Answer 2

i.e.
\[b^2-4ac>0\] with \(a=k,b=-10,c=5k\)

Answer 3

A quadratic equation ax^2 + bx + c = 0 has two roots when the discriminant of the quadratic formula is positive. The discriminant is b^2 - 4ac. In your case, a = k, b = -10, and c = 5k. Plug those values into the discriminant and set it greater than zero and solve the inequality.

Answer 4

... where'd you get that formula?
satelite?

Answer 5

It's what's inside the radical of the quadratic formula.

Answer 6

that's what I was forgeting! discriminate! I kept solving it wrong! thanks!

Answer 7

it is the discriminant, that is \(b^2-4ac\) from the term inside the radical in the quadratic formula
is it clear how to solve
\[100-20k^2>0\]?

Answer 8

Sorry, I'm back... So I now have But where do I go from here?