Final answer:
To find the dimensions of Cleopatra's solid-gold jewelry box with a perimeter of 230 cm and the length being 21 cm less than triple the width, we calculate the width as 34 cm and the length as 81 cm.
Step-by-step explanation:
To solve for the dimensions of Cleopatra's solid-gold jewelry box, we'll use the information provided about the perimeter and the relationship between the length and the width. Let's let w represent the width of the box, then the length l would be 3w - 21 centimeters. The formula for the perimeter P of a rectangle is P = 2l + 2w. Substituting the known values:
- The perimeter P is given as 230 cm.
- The length l in terms of width w is 3w - 21 cm.
Now we can set up the equation:
230 = 2(3w - 21) + 2w
Expanding this, we get:
230 = 6w - 42 + 2w
Combining like terms:
8w - 42 = 230
Add 42 to both sides:
8w = 272
Divide both sides by 8:
w = 34
Now that we have the width, we can find the length:
l = 3(34) - 21
l = 102 - 21
l = 81
Therefore, the width of Cleopatra's solid-gold jewelry box is 34 centimeters and the length is 81 centimeters.