There's not enough information to answer this question. The height needs to be known as well.
700cm
The width is 10.5 cm.
Do-it-in-your-head method: Length plus width is half the perimeter ie 161 cm, of which 68 is width so the length is 93 cm.
32 cm
Suppose the width is W cm. Then the length is 3W cm. THerefore, the perimeter is 2*(3W + W) = 8W = 56 So W = 7 cm.
2(y-6)+2y=64 2y-12+2y=64 4y-12=64 4y=76 y=19 width: 19 cm.
30 cm.
Perimeter of Rectangle = 2(length + width) =2(45+30) =150 cm
The perimeter is two times the sum of the width and length expressed in cm. The area is the length times the width expressed in square cm.
The length works out as 12 cm and the width works out as 5 cm Check: 2*(12+5) = 34 cm which is the perimeter
150cm
Length + width = 18 cm so length = 12 cm and width = 6 cm. Presumably the length is the common side so the perimeter of the octagon is 8 x 12 = 96 cm. If the width is the common side then the perimeter of the octagon is 8 x 6 = 48 cm
32 cm
150 cm
18cm is the area and perimeter. the width is 3cm.
16.4
700cm