To solve this inequality, we have to isolate x on one side. Whatever we do to the equation we have to do it on both sides.
1.30x + 5.20 ≤ 18.20
Subtract 5.20 from both sides.
1.30x + 5.20 - 5.20 ≤ 18.20 - 5.20
1.30x ≤ 13
Divide by 1.30 on both sides.
1.30x/1.30 ≤ 13/1.30
x ≤ 10
Antoine can buy 10 pounds of oranges.