3x^2+2=-8x <--- solve by the quadratic formula , set the equation to "0" first. must be in simplest radical form, show work please
coefficients are a = 3 b = 8 c = 2 substitute these into quadratic formula
how i get the equation to equal to zero first?
just add 8x to both sides.
i got x=\[\pm8\]\[\sqrt{8^2-4(3)(2)}\] /2(3) is that right?
Should be \[x = \frac{-8 \pm \sqrt{8^2-4(3)(2)}}{2(3)}\] So yeah, the 8 out front is negative, and the plus or minus goes between the -b and the square root. Otherwise that's right.
so what would i do next?
Do the multiplication in the square root part and the denominator, then simplify it.
x=-8 \[\pm\] \[\sqrt{8^2-36}\]/6
is that right?
4(3)(2) = 24\[\implies \sqrt{8^2 - 4(3)(2)} \]\[= \sqrt{8^2 - 24} \]\[= \sqrt{64 - 24}\]\[=\sqrt{40}\]\[=\sqrt{4\cdot 10} \]\[=2\sqrt{10}\]
so you can replace the square root you have with 2 root(10)
how you get 24?
would we put the -8 and that upside down tee looking like before the square root problems you did?
that upside-down t is called the plus or minus sign. and yes.
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