

- <u>The </u><u>sum</u><u> </u><u>of </u><u>the </u><u>number </u><u>in </u><u>each </u><u>of </u><u>the </u><u>four </u><u>rows </u><u>is </u><u>the </u><u>same </u>
- <u>The </u><u>sum </u><u>of </u><u>the </u><u>numbers </u><u>in </u><u>each </u><u>of </u><u>the </u><u>three </u><u>columns </u><u>is </u><u>the </u><u>same</u>
- <u>The </u><u>sum </u><u>of </u><u>any </u><u>row </u><u>does </u><u>not </u><u>equal </u><u>the </u><u>sum </u><u>of </u><u>any </u><u>column </u>

<u>According </u><u>to </u><u>the </u><u>Second</u><u> </u><u>rule </u><u>:</u><u>-</u>


<u>According </u><u>to </u><u>the </u><u>first </u><u>rule </u><u>:</u><u>-</u><u> </u>


<u>From </u><u>(</u><u> </u><u>1</u><u> </u><u>)</u><u> </u><u>we </u><u>got </u><u>:</u><u>-</u>



<u>Subsitute </u><u>(</u><u>3</u><u>)</u><u> </u><u>in </u><u>(</u><u> </u><u>2</u><u> </u><u>)</u><u> </u><u>:</u><u>-</u>


<u>We</u><u> </u><u>can </u><u>write </u><u>it </u><u>as </u><u>:</u><u>-</u>



<u>Subsitute </u><u>the </u><u>value </u><u>of </u><u>c </u><u>and </u><u>e </u><u>in </u><u>(</u><u> </u><u>1</u><u> </u><u>)</u><u>:</u><u>-</u>


<u>Now</u><u>, </u>









Hence, The value of a, b, c, d and e is 23, 31 ,60 ,33 and 51 .
The absolute value of 78 is < the absolute value of -222
She will have $57 back because the ticket are buy one get one free and she has 7 friends so for 3 tickets that u buy 6 of your friend get to go and then thei is still one more friend so you have to buy one more ticket so 10.75*3=32.25
and 32.25+10.75=43 and 100-43=57
Step 1. Multiply first equation with -3 and the second one with 2. You'll get:

Step 2. Add both equations together. You'll get:

, which gives x = -2
Step 3. Replace x = -2 in the first equation and calculate y.

The solution is: x=-2, y=5