Question

Does anyone know how to know which of the graphs of these equations has no x-intercepts?

a)6x^2+2x-5=0
b) 4x^2-3x+1=0
c)4x^2-7x+3=0
d)x^2+8x-3=0

Answer 1

check their roots, see which ones give you imaginary values

Answer 2

imaginary values, means it has no x-intercepts or roots

Answer 3

wait, how do u check its root?

Answer 4

\[x=\frac{ -b \pm \sqrt{b^2-4ac} }{ 2a }\]

Answer 5

hmm well, you can always use the quadratic equation for one

ahemm.... anyhow.. the exercise assume you know how to factor quadratics

Answer 6

I assume you dunno the quadratic equation?

Answer 7

oh I know the quadratic equation, but how does it help to find the x-intercept?