This led me to the equation (w-2)(w+4) = 160, but this leads to a quadratic that isn't factorable and I tend to doubt that was the intention. Is this equation correct?

- Thread starter mauricev
- Start date

This led me to the equation (w-2)(w+4) = 160, but this leads to a quadratic that isn't factorable and I tend to doubt that was the intention. Is this equation correct?

- Joined
- Nov 12, 2017

- Messages
- 4,156

Actually it is factorable. What convinced you that it is not?

This led me to the equation (w-2)(w+4) = 160, but this leads to a quadratic that isn't factorable and I tend to doubt that was the intention. Is this equation correct?

But why does it have to be factorable? You can always solve the equation by the quadratic formula (unless you haven't learned it yet); you wouldn't get nice integer dimensions, but that happens only when a teacher is being nice to you -- not in the real world!

You're right. MathPapa led me to believe--erroneously--it wasn't.Actually it is factorable. What convinced you that it is not?

But why does it have to be factorable? You can always solve the equation by the quadratic formula (unless you haven't learned it yet); you wouldn't get nice integer dimensions, but that happens only when a teacher is being nice to you -- not in the real world!

- Joined
- Nov 12, 2017

- Messages
- 4,156

I hadn't heard of the site, perhaps for good reasons.You're right. MathPapa led me to believe--erroneously--it wasn't.

Note that if you think a quadratic trinomial might not be factorable, you can check by calculating the discriminant. If it is a perfect square, then the trinomial is factorable; then you can either factor it, or continue with the quadratic formula.

w^2+2w-168=0What quadratic equation did you get from that?

(x-12)(x+14)=0

Make that (w - 12)(w + 14) = 0w^2+2w-168=0

(x-12)(x+14)=0