Stuck on Algebra Problem

[P.Q.]

mathreview.universalclass.com/secure/406/7550574/download/images/Assignment7.jpg



For mathreview.universalclass.com/secure/406/7550574/download/images/Assignment6.jpg i need help understanding how

PerfectionxQueenie: i can sort of get how to do 5/6 +5/8 but you multiply them to get the solution so 6 and 8 would be the same number but would it be the same kind of multiplication for 4/5*15/16 ?
It would be 2a^2+b

PerfectionxQueenie: how would it be 2a ^2+b?

PerfectionxQueenie: I have a test coming up and need to know how to do all these problems >o<



xotrinaxo4: 2 is



3x^2-4y^2-z^2

3 is...

PerfectionxQueenie: but why

PerfectionxQueenie: D:

PerfectionxQueenie: how did you come up with those answers

You just add the coeifficients

the numbers in front are coefficents

and you only add and subtract like terms

so if they're to different powers...you can't add or subtract them

PerfectionxQueenie: but then why do you take out -c when adding the first problem

For multiplication you have to multiply the powers together though



you wouldn't

it would be -2c

if there isnt a number in front, you treat it like one

PerfectionxQueenie: there is a number in front
not for number one?

it's just (-c+-c)

PerfectionxQueenie: a2+b-c ) then (a2-c)

yes?

So really you look at it like...

: (1a^2+1b-1c) + (1a^2-1c)

: Got it?


: So start with a....it would be (1a^2+1a^2)

PerfectionxQueenie: then that one would be 3a+2bc+3ac?

PerfectionxQueenie: D:

: no.

PerfectionxQueenie: i dont get what you have to do

: it's adding.

: not multiplying

: So break it up into like terms

PerfectionxQueenie: i thought you were adding the numbers

: only add the like terms

: like (1a^2+1a^2) = 2a^2

PerfectionxQueenie: ok so you add 1a with 1a?
: then (1b + 0) = 1b

: Yess.

: (:

PerfectionxQueenie: like the first two parts and leave the last part :3

: Like terms go together

PerfectionxQueenie: I think I get it now

PerfectionxQueenie: thanks

: Multiplication and division are different though

PerfectionxQueenie: how

: For multiplication...you have to add the powers together

and for division you subtract the powers



PerfectionxQueenie: so like if this was multiplication (1a^2+1a^2) instead of 2a^2 it would be (3a^+3a^)

PerfectionxQueenie: ?

: no

: it would be 2a^4

: you add the coefficiants...so 1+1=2

: 2a...



: and then add the powers

: 2+2

: 2a^4

[P.Q.]

Okay for assignment 6
mathreview.universalclass.com/secure/406/7550574/download/images/Assignment6.jpg
This one's a bit tricky, since there is a minus sign before the second pair of brackets. You have to do it like this:

(6s^3 + 4s^2 + 3s - 12) - (2s^3 - 2s^2 + 5s - 9)
But why do you have to put the ^ and why do you leave out the first bracket?
6s^3 + 4s^2 + 3s - 12 - (2s^3 - 2s^2 + 5s - 9)

why do you have to multiply the numbers between the second pair of brackets with -1. If there's a minus sign before the brackets shouldn't you be taking numbers out?

6s^3 + 4s^2 + 3s - 12 - 2s^3 + 2s^2 - 5s + 9

How do you figure that it will add up to:

4s^3 + 6s^2 - 2s - 3

Wouldn't multiplying it just make the number much higher?

6s^3 + 4s^2 = 10s^5 + 3s - 12 - 2s^3 = 1s ^ 9 +10s^5=11s ^ 14 + 2s^2 - 5s + 9 = 3s 7 wouldn't it?
or are you just adding the terms? D:
But wouldn't it be s5 then?

+++++++++++++++++++++++++++++
why do you have to multiply all numbers in the left pair of brackets with the numbers in the right pair of brackets and then multiply everything, didn't you already just multiply everything by doing that?
So with (2a - 4b - 3c)(4a + 4b + 5c) you'll get:
2a(4a + 4b + 5c) - 4b(4a + 4b + 5c) - 3c(4a + 4b + 5c) then

(8a^2 + 8ab + 10ac) - (16ab + 16b^2 + 20bc) - (12ac + 12bc + 15c^2)
is because 2 x 4 = 8? but how do you figure there's a 2? If you multiply it, the numbers will always be higher then what it was.
After this it's really easy. Just count everything up and you'll get:

8a^2 - 8ab - 2ac - 16b^2 - 32bc - 15c^2 ( What do you mean by count everything?, it doesn't look like you counted everything together, when you count you count upwards. how did you get 32bc?)

++++++++++++++++++++++++++++++++
9 requires some logical thinking.

You have 2 numbers, let's call them x and y. y is one more than x. So y is the larger integer, and x the smaller one.
The sum, written down algebraic, is like this:
y^2 = xy + 17 (I can sort of understand this one if there is two numbers one is lower than 17 and then you divide by y but how do you figure that 2 is y? Wouldn't it be 8.5? because you divide 2 from 17? If anything I think the answer would be half of 17. )

[P.Q.]

www.brightstorm.com/math/algebra-2/roots-and-radicals/multiplying-complex-numbers/


www.brightstorm.com/math/algebra-2/roots-and-radicals/dividing-complex-numbers/

Check out those, This helps.

[P.Q.]

"Having said that, I believe that advice should be taken with brushing up on the basics and hammering it into your brain. They key to math is understanding, not just knowing. When you truly understand why it is so, you will know instantly whether your answer is correct or not. And you will not have to memorize things like the quadratic formula, because when you understand, you can derive it yourself. When you understand, algebra is easy because you know that if you have several of the same letters as unknown numbers, you know they are the same number. You will know that 4y is four multiplied by y, and 4y - 3y = y, because it is the equivalent of y x y x y x y - y x y x y. (Try this: let y be equal to 2).

The point I am trying to make is to understand, not just know how to do stuff in math."