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3 years ago

8

Please help really confused on all

1 answer:

ollegr [7]3 years ago

5 0

$\left \{ {{x - y = 1.50} \atop {40x + 40y = 940}} \right. 
 \\ \\
*x - y = 1.50$

x = 1.50 + y

*40x + 40y = 940
40 (1.50 + y) + 40y = 940
60 + 40y +40y = 940
60 + 80y = 940
80y = 940 - 60
80y = 880
y = 880/80
y = 11

*x - y = 1.50
x - 11 = 1.50
x = 1.50 + 11
x = 12.5

x=DAVID
Y=PETER

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3 years ago

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8_murik_8 [283]

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