How many solutions does the system have? ⎪
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x+y=3
5x+5y=15
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X=3-y

5(3-y) + 5y=15

15y-5y+5y=15

15y=15

Y= 15/15

Y= 1

X+(1)=3

X=3-1

X=2

Final x=2 and y=1

Method: simultaneous equations

So don't take my word i'm not exactly a mathematical person but i would assume a. because while selling the soap every month you increase in sells so you would by 11 percent. the you would get the factor 0.89 which if i had to guess would be the monthly profit over 11 probably wrong tho