Originally Posted by

**skeeter** no, they are not correct.

$\displaystyle 5.71x^2 - 3.135x - 5.64 = 0$

learn to use the store capability of the calculator. the "store" button is just above the ON button labeled [STO->] ... type the number first, hit the store button (you get the arrow), then type in the letter of the alphabet where you want it. A, B, and C are good choices since they represent the values in the quadratic formula.

5.71 -> A

-3.135 -> B

-5.64 -> C

now type in on the home screen ...

$\displaystyle (-B + \sqrt(B^2 - 4AC))/(2A)$

for one the first root.

{note that the negative sign in front of B is the small negative sign, whereas the minus sign between B^2 and 4AC is the subtraction sign}

press [2nd][ENTER] to recall the last expression, change the + to a - ...

$\displaystyle (-B - \sqrt(B^2 - 4AC))/(2A)$

for the second root.

you should get 1.305586355 and -.7565495776