Donna sold 3 pencils and 8 pens solved using simultaneous equation
What is a simultaneous equation?
Simultaneous equation refers to related equations that are solved at the same to derive answers to the unknown variables
Let assume that X pencils were sold and Y pens were sold
The total revenue is the sum of the prices multiplied by the quantities sold.
2X+3Y=30 (equation 1)
The sum of X and Y sold is 11
X+Y=11 (equation 2)
multiply the second equation by 2
2*(X+Y=11)
2X+2Y=22 (equation 3)
subtract equation 3 from 1
(2X+3Y=30)-(2X+2Y=22)
Y=8
Substitute for Y in equation 2
X+8=11
X=11-8
X=3
Which means he sold 3 pencils and 8 pens.
Find details on simultaneous equation in the link below:
brainly.com/question/20627346
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