SOLUTION: how many x intercepts does this equation have? y=4x^2+x+2

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Question 967848: how many x intercepts does this equation have? y=4x^2+x+2
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
y = 4x^2 + x + 2
it's a quadratic so you can factor it.
easiest way is to graph it.
graph looks like this:
graph%28400%2C400%2C-10%2C10%2C-10%2C10%2C4x%5E2%2Bx%2B2%29
it doesn't cross the x-axis.
without graphing, you would have had to solve.
give it the discriminant test.
discriminant is b^2 - 4ac
equation is 4x^2 + x + 2 = 0
a = 4
b = 1
c = 2
b^2 - 4ac = 1 - 4*4*2 which is negative.
distriminant is negative so the roots are not real.
roots are not real so the graph goesn't cross the x-axis.