Question

what is X^2-3x=28 my answer is (x-7)(x-4) am I correct

Answer 1

No, I don't think so. If you FOIL, you can check your answer.

Answer 2

what is foil :)

Answer 3

First you want to have all terms on the same side of the = sign, so -28 from both sides.

Answer 4

We will get to FOIL in a minute. I'll walk you through the steps to answer this question.

Answer 5

thnx

Answer 6

\(X^2-3x=28\) First, you want the 28 on the left side of the equal sign.

Answer 7

following keep going :)

Answer 8

\(x^2-3x-28=0\) To factor, start with the \(x^2\) term. This one is easy since the coefficient is 1.
(x )(x )

Answer 9

Now you need to find 2 numbers that multiply to be -28 and add to be -3

Answer 10

What do you think they are?

Answer 11

-7 and +4

Answer 12

Yes, now you can write your factors....

Answer 13

x-7 x +4

Answer 14

x-7 x+4

Answer 15

\((x+4)(x-7)\) And to check your work - use FOIL
First = \(x \times x = x^2\)
Outside = \(-7 \times x = -7x\)
Inside = \(4 \times x = 4x\)
Last = \(-7 \times 4 = -28\)

Answer 16

Put it all together and you should get back to your original equation.

Answer 17

neat concept awesome you get a medal for that :) thnx bunches

Answer 18

Your welcome.