Multiply you first equation by 2 to get 4x + 10y = 22
Now the x terms can be eliminated and cancelled out using elimination.
4x + 10y = 22
4x + 3y = 1
To eliminate you need to "subtract", so you need to multiply one of the equations by -1.
4x + 10y = 22
-4x -3y = -1
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0 + 7y = 21
y = 3
Now plug 3 into either one of the equations to get x.
I believe the answer is 4/15.
All you have to do is add 125 by 75 and you get 200. Now you have to subtract 500 by 200 which is 300 and here you go your answer is 300. The bookstore has to sell 300 more books in order to sell 500 books by friday
I round the answer to the second digit and get 18.33
Here is the expansion of <span>(x + y)n </span><span>for </span><span>n = 0, 1,…, 5</span><span> :</span>
<span>(x + y)0 = 1</span>
<span>(x + y)1 = x + y </span>
<span>(x + y)2 = x 2 +2xy + y 2 </span>
<span>(x + y)3 = x 3 +3x 2 y + 3xy 2 + y 3 </span>
<span>(x + y)4 = x 4 +4x 3 y + 6x 2 y 2 +4xy 3 + y 4 </span>
<span>(x + y)5 = x 5 +5x 4 y + 10x 3 y 2 +10x 2 y 3 +5xy 4 + y 5
</span>
hopefuly this helps you understand