Question 1056580
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Use elimination to solve each system of equations. I have to show all work and write the answer as an (x,y) ordered.

7x+4y=-4
5x+8y=28
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<pre>
7x + 4y = -4,      (1)
5x + 8y = 28.      (2)

Multiply equation (1) by 5 (both sides).
Multiply equation (2) by 7 (both sides). You will get

35x + 20y = -20,   (1')
35x + 56y = 196.   (2')

Distract (1) from (2) (both sides). You will get

56y - 20y = 196 - (-20),   (<--- you got a single equation for only one unknown. It is how ELIMINATION method works !)

36y = 216,

y = {{{216/36}}} = 6.

Thus you just found "y".

Then from (1) 7x = -4 - 4y = -4 -4*6 = -28.

x = {{{(-28)/7}}} = -4.

<U>Answer</U>.  x = -4,  y = 6.
</pre>

On Elimination method see the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF = http://www.algebra.com/algebra/homework/coordinate/lessons/Solution-of-the-lin-syst-of-two-eqns-with-two-unknowns-Elimination-method.lesson>Solution of a linear system of two equations in two unknowns by the Elimination method</A> 

in this site.