Question

What are the solutions of 3x2 + 4x = –5?

the quantity negative 4 plus or minus i square root of 66 all over 6

the quantity negative 2 plus or minus 2i square root of 66 all over 3

the quantity negative 2 plus or minus i square root of 11 all over 3

the quantity negative 4 plus or minus i square root of 11 all over 6

Answer 1

Did you put it equal to 0 and plug into the quadratic formula?

Answer 2

3x^2+4x+5=0

Answer 3

3x^2 + 4x = –5
3x^2 +4x +5 =0
Now, use the quadratic formula for the equation.
\[x= \frac{-b \pm \sqrt{b^2 -4ac}}{2a}\]
Put a =3, b=4 and c=5 into the formula. Can you do it?

Answer 4

is it the first option?

Answer 5

the quantity negative 4 plus or minus i square root of 66 all over 6?

Answer 6

Not really...
Just consider the determinant b^2 - 4ac
For a =3, b=4 and c=5 ,
b^2 - 4ac = 4^2 - 4 (3) (5) = 16 - 60 = ?