The perimeter of rectangle is 14 feet and its length is l and width is w.

Write the equation by using perimeter formula of rectangle is .

The word twice its length l is equal to 1 less than 4 times its width w represent the equation is .

The equations of linear system are .

Rewrite the equation 2: so that the like terms are arranged in column.

Subtract 4w from each side.

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Since the coefficient of the l - term in the above two equations is same, eliminate these terms by subtracting the equations.

Write the equations in column form and subtract to eliminate variable l.

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The resultant equation is and solve it for w.

Divide each side by 6.

Cancel common terms.

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Substitute the value of in equation 2: and solve for l.

Divide each side by 2.

Cancel common terms.

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The length of the rectangle is 4.5 feet and its width is 2.5 feet.