Question

Which part of the quadratic formula tells you whether the quadratic equation can be solved by factoring?

−b b2 − 4ac 2a

Use the part of the quadratic formula that you chose above and find its value given the following quadratic equation:

2x2 + 7x + 3 = 0

Answer 1

The discriminant. b^2-4ac must be >0 for real number factors.

Answer 2

It's [b ^{2}-4ac\] But I don't remember why or how.

To solve it it's easy, think of your equation in this way:
a is paired with x because x is earlier in the alphabet, so is a
b is paired with y because y is after x in the alphabet, as is b to a
and c is always your number on it's own.

Answer 3

no idea how to do this its a pretest i just need a numerical answer to the second part

Answer 4

Don't you have the quadratic formula?

Answer 5

You can also do it by grouping

Answer 6

You just have to plug the numbers from the equation they gave you into the answer you chose for the first part and solve it.

Answer 7

Actualy, grouping is not going to work here. Use the quadratic formula

Answer 8

if i seen it i would understand

Answer 9

The whole quadratic formula isn't needed, just the part of the equation picked in part 1.
Take the b^2 - 4ac and put in the values of b, a, and c and compute it using a calculator.

Answer 10

Oh yes, only the discriminant is needed. Skimmed that part.

Answer 11

The second part of the question is asking you to find
b^2 - 4ac

So you need to find a,b, and c, and use the above formula
the a, b, and c come from
a x^2 + bx + c
so match your quadratic
2x^2 + 7x + 3 = 0

to find a,b, and c.