Math Help 2

[heedicalking]

I could use an explanation on some things.

Factoring Binomials/Trinomials. When I took Algebra I, our teacher left tons of sections out, so I'm stuck still needing to learn things that I should already know.

x^2 + 5x + 4 how do I solve it?

[Ad Bot]

[Joker Card]

(x+4) (x+1)

x^2 + 4x +1x +4

x^2 +5x +4

[heedicalking]

I could still use explanation on how to solve it.

What about this one, since it seems easy:
x^2 - 1

[rkynick]

(x+1)(x-1)


When you multiply (x+1) and (x-1)
The first terms multiply: x²
The first and last multiply: -1x
The middle terms multiply: 1x
The last terms multipy: -1
Add them all together:
x²-1

To get from x²-1 to (x+1)(x-1)
You find two numbers that add to be b and multiply to be c in
ax²+bx+c

So in this case -1 and +1: adds to be 0 (b) and multiplies to be -1 (c)
Which becomes (x+1)(x-1)

[Illidan]

the way i learned it was this way:

x^2 + 5x + 4

the factors in this case would be (x+4) and (x+1)

now, look at the trinomial this way:

ax^2+bx+c

the two factors, when multiplied, add up to the value of c (in this case: 4)
and when added they add up to the value of b (in this case: 5)

there's also another method of checking the factors called FOIL (First, Outer, Inner, Last)
meaning you multiply the first two numbers (x times x), then the outer numbers (x times 1), then the inner (4 times x), and then the last (1 times 4)

which would all come out to be the trinomial you gave

[steve5451]

I am too DUMB for this thread! Aahhgg!

[heedicalking]

Radicals:

3√27 would be 3?

What about

√1/6 (1/6 is a fraction, the square root symbol covers the whole fraction)