Step-by-step explanation:
l= 3x+2cm
b=4cm
Perimeter of the rectangle= 68cm
Now, according to the formula, the perimeter of a rectangle= 2(l+b)
Therefore,
2(l+b)=68
2{(3x+2)+(4)}=68
2{3x+2+4}=68
2{3x+6}=68
6x+12=68
6x=68-12
6x=56
x=56/6
x≈9.33
In order to cross-check this answer, we compute in the values so therefore,
3x+2=3(9.33)+2=27.99+2=29.99≈30
Now, substituting this value in the formula we get,
2(30+4)= 68
The reason for cross-checking was to re-assure because of the decimal value of 9.33, that is why I approximated the expression to 30 in order to get the exact value of 68. otherwise using the decimal value of 9.33 computes an answer of 67.98 which off by a difference of 0.2.
