Medal given!
Question 1:Solve the following system of equations by using the multiplication method:
2x - 7y = 9
3x - 4y = -6

Question 2:Solve the following system of equations using multiplication method:
5x + 3y = 1
x + 2y = 10. Show your work

Question

Medal given! 
Question 1:Solve the following system of equations by using the multiplication method: 
2x - 7y = 9 
3x - 4y = -6 

Question 2:Solve the following system of equations using multiplication method: 
5x + 3y = 1 
x + 2y = 10. Show your work

aaronq · Answer

The purpose of multiplying the equations is that you end up with the same variable with the same coefficient so when you add them they cancel out and you're left with only one.
I'll do the first one:

(1) 2x - 7y = 9 
(2) 3x - 4y = -6 

Multiply  (1) by -3 and (2) by 2

(1) -6x + 21y = -27 
(2) 6x - 8y = -18 

Now add them: -6x+6x + 21y -8y= -27 + ( -18)

13y=-45   y= $\dfrac{-45}{13}$

You can find x by pluggin this into the prior equation 

6x - 8( $\dfrac{-45}{13}$) = -18

$x=\dfrac{21}{13}$

aaronq · Answer

oh wait i made a mistake.

(1) -6x + 21y = -27 
(2) 6x - 8y = $\color{red}{-12}$

aaronq · Answer

so, $y=-3$

 -6x + 21y = -27 

 -6x + 21(-3) = -27 

$x=-6$

anonymous · Answer

That actually helped me out a lot.. Thank you, I understand how to do those now @aaronq

anonymous · Answer

Can you help me with another? @aaronq

aaronq · Answer

No problem, glad i could help! 

sure post away

anonymous · Answer

Find - 3x2y(6x2y2 - 8x +12y)
Choose one answer.
	 a. -9 x3y3 - 8x3y +12x2y2	
	 b. - 18x4y3 + 24x3y + 36x2y2	
	 c. - 9x4y3 + 11x3 + 36x2y	
	 d. - 18x2y3 -11x3y - 15x2y2

aaronq · Answer

is it this?   $ - 3x^2y(6x^2y^2 - 8x +12y)$

aaronq · Answer

i mean the original function with the exponents

anonymous · Answer

Yess

aaronq · Answer

k, so you pretty much have to distribute the $ - 3x^2y$ at the front.

you can do it one at a time or all at once. 

I'll do it one at a time first. 

 $ - 3x^2y(6x^2y^2 - 8x +12y)$

$ x^2y[(-3)*6x^2y^2 - (-3)*8x +(-3)*12y]$

$ x^2y[-18x^2y^2 +24x -36y]$

now the x^2

$ y[-18x^4y^2 +24x^3 -36yx^2]$

now the y

$ -18x^4y^3 +24x^3y -36x^2y^2$

anonymous · Answer

Oman.. I feel really dumb. That's like the easiest thing to do in this whole class ahhaha. Thanks for breaking it down ;p

aaronq · Answer

haha dont feel dumb. You should do these things on actual paper, it's much much easier to see  as long as you keep things neat. No problem though !