Question 267296
-2x+5y=20 multiply by 3
3x-7y=-26 multiply by 2 & add.
-6x+15y=60
6x-14y=-52
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y=8 ans.
-2x+5*8=20
-2x+40=20
-2x=20-40
-2x=-20
x=-20/-2
x=10 ans.
Proof:
3*10-7*8=-26
30-56=-26
-26=-26