Step-by-step explanation:
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9+3t is your answer.......
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
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hopefuly this helps you understand
10% of $20 is $2 (take off the end 0)
$20+10%=?
$20+$2[this is 10%]=$22
The selling price is $22