Question

B. The perimeter of this rectangle is 20 centimeters. What is the value of X

Answer 1

Statement Problem: Find the value of x in the diagram below, given the perimeter of a rectangle as 20centimeters.

Solution:

The perimeter of a rectangle is;

`P=2(l+w)`

Where the length and width of the given rectangle is;

`\begin{gathered} l=(x+3)cm \\ w=(x+1)cm \end{gathered}`

Thus, the value of x is;

`\begin{gathered} 2(l+w)=20 \\ 2(x+3+x+1)=20 \\ \text{Divide both sides by 2},\text{ we have;} \\ (2\mleft(x+3+x+1\mright))/(2)=(20)/(2) \\ x+3+x+1=10 \\ \text{Collect like terms, we have;} \\ 2x+4=10 \\ \end{gathered}`

Then, we subtract 4 from both sides of the equation, we have;

`\begin{gathered} 2x+4-4=10-4 \\ 2x=6 \\ \text{Divide both sides by 2, we have;} \\ (2x)/(2)=(6)/(2) \\ x=3 \end{gathered}`

The value of x is 3