Answer:
length: 30 meters
width: 12 meters
Step-by-step explanation:
2(a+b) = 84
a = 2b + 6
a = length
b = width
then:
2((2b+6)+b) = 84
2b + 6 + b = 84/2
3b + 6 = 42
3b = 42 - 6
3b = 36
b = 36/3
b = 12
a = 2b + 6
a = 2*12 + 6
a = 24 + 6
a = 30
Check:
84 = 2(12+30)
84 = 2*42