Question

Jack is building a rectangular fence for his ferret. He has 20 feet of fencing and wants the short side of the fence to be 7/2 feet. How long will the other side of the fence be? Write the answer in decimal form.

Answer 1

General Idea:

When we are working with word problems, we need to follow the below steps:

Step 1: Assign variable for the unknown that we need to find.

Step 2: Write a meaningful mathematical equation using the sentence given

Step 3: Solve the equation by Performing reverse operation by Undoing whatever is done to the variable. Solving means find the value of the variable which will make the equation TRUE.

Applying the concept:

Step 1: Let 'x' be the length of longest side of the fence.

Step 2: We need to set up an equation based on the information given.

$Perimeter\; of\; rectangle=\; 2(\; Longest \; side\; +\; Shortest \; side\; )$

Substituting 20 for the perimeter of rectangle, x for Longest side and $\frac{7}{2}$ for the shortest side in the above formula, we get the below equation.

$2(x+\frac{7}{2} )=20$

Step 3: Solving the equation.

$2(x+\frac{7}{2} )=20\\ Distribute \; 2 \; in \; the \; left \; side \; of \; the \; equation\\ \\ 2x+2 \cdot \frac{7}{2} =20\\ Simplify \; in \; the\; left\; side \; of \;the \;equation\\ \\ 2x+7=20\\ Subtract \; 7 \;on\; both \;sides \; of\; the \; equation\\ \\ 2x+7-7=20-7\\ Combine\; like \; terms\\ \\ 2x=13\\ Divide \; by \; 2\;on \; both\; sides\\ \\ \frac{2x}{2} =\frac{13}{2} \\ Simplify \; fraction\;on \; both \; sides\\ \\ x=6.5$

Conclusion:

The length of longest side of the fence is 6.5 feet.

Answer 2

Jack wants the short side of the fence to be 7/2 feet.

the other side of the fence will be 6.5  feet