this is 6th grade work there will be more questions on this but i needed help on this
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Answer:
Step-by-step explanation:
X + (X + 4) + (X - 7) = 54
3X - 3 = 54
3X - 3 + 3 = 54 + 3
3X = 57
3X / 3 = 57 / 3
X = 19
Y = (19 + 4) = 23
Z = (19 - 7) = 12
Sam's age = 19
Dana's age = 23
Alex's age = 12