Question 513746
Let:  L=Length and W=Width
Perimeter = 2L + 2W
58 = 2(6) + 2W 
58 = 12 + 2W
58 = 12 + 2W
58 -12 = 2W -12 + 12
46 = 2W
46/2 = 2W/2
23 = W