(X,Y) is (20,10) so that mean he made 10 bucks and sold 20 cups
A rational number is any number that can be expressed as the quotient or fraction p/q of two integers, a numerator p and a non-zero denominator q. Since q may be equal to 1, every integer is a rational number. I dont know about the other question
Answer:
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Step-by-step explanation:
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5
4x+15y=13 (1)
3x+5y=16 (2)
(2) * 3 --> 9x+15y=48 becomes (3)
(3) - (1)
5x=35
x=7
sub x =7 into (1)
4(7)+15y=13
28+15y=13
-28 -28
15y= -15
y= -15/15
y= -1
therefore x=7 and y= -1