a rectangle has a width of 45 centimeters and a perimeter of 188 centimeters. What is the rectangles length?
a rectangle has a width of 45 centimeters and a perimeter of 188 centimeters. What is the rectangles length?
perimeter p = 188 cm
width w = 45 cm
length l = ? cm
\(\begin{array}{rcll} p &=& 2w + 2l \qquad & | \qquad w = 45\qquad p= 188\\ 188 &=& 2 \cdot 45 + 2l \\ 188 &=& 90 + 2l \qquad &| \qquad -90\\ 188-90 &=& 2l \\ 98 &=& 2l \\ 2l &=& 98 \qquad &| \qquad :2\\ l &=& \frac{98}{ 2} \\ l &=& 49 \\ \mathbf{\text{length} }&\mathbf{=}& \mathbf{49\ \text{cm}} \end{array}\)