Explanation:
so first you combine like terms , 3x-x-4=4 turns into 4x-4=4 then u add 4 to both sides [inverse operations]
4x-4=4
+4 +4
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4x= 8
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4. 4
×=2
then u use inverse operations. agian and divide 4 into 8 and you get 2 !! x = 2