Answer: ? = x + 1
Explanation:
The perimeter of the garden is x + 3x + 1 + x + ?
The perimeter of the garden is also (6x + 2)
Therfore:
x + 3x + 1 + x + ? = 6x + 2
Collect like terms:
5x + 1 + ? = 6x + 2
Subtract 5x from both sides:
1 + ? = x + 2
Subtract 1 from both sides:
? = x + 1
You cannot find ? as a number, only in terms of x.