4x=10+5y

2x+5y=10/(-2)

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4x-5y=10

-4x-10y=-20

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-15y=-10, 15y=10, y=10/15, y=2/3

4x=10+5×(2/3),4x=10+10/3, 4x=40/3, x=10/3

x=10/3 , y=2/3

L1=4×10/3=40/3, P1=10+10/3=40/3, L1=P1

L2=20/3+10/3=30/3=10, P2=10, L2=P2