Answer:
6w +8 ≥70
Explanation:
Let w be the width
The length is then 3w+4 ("the length is 4 more than 3 times the width")
Since a rectangle has opposite sides equal, the perimeter would be 2(l+w) or 2(w+3w+4) which would be 6w +8. If the perimeter is at least 70, that is, 70 or more, the inequality would be
6w + 8 ≥ 70.
The units, however, would not be SQUARE centimeters, just centimeters. If the question were asking for area, the units would be square units, but since perimeter is a linear measurement, the units would have to be linear.