Answers

2015-08-31T08:22:55+08:00
Php 7
let x=cost of 1 pencil
let y=cost of 1 pen
2x+3y=50
3x+2y=45
Subtracting the two equations we get
y-x=5
y=x+5
substituting y into one of the two equations
2x+3(x+5)=50
2x+3x+15=50
5x+15=50
5x=50-15
5x=35
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5 5
x=7
2 3 2