Express w in terms of l: From the first equation, we can express w in terms of l: w=8−l.
Substitute into Area Equation: Substitute w=8−l into the second equation: 15=l(8−l).
Expand and Rearrange: Expand the equation: 15=8l−l2.
Form Quadratic Equation: Rearrange the equation to form a quadratic equation: l2−8l+15=0.
Factor Quadratic Equation: Factor the quadratic equation: (l−5)(l−3)=0.
Solve for l: Solve for l: l=5 or l=3.
Find Dimensions: If l=5, then w=8−l=8−5=3. If l=3, then w=8−l=8−3=5.
Find Dimensions: If l=5, then w=8−l=8−5=3. If l=3, then w=8−l=8−3=5.We have two possible dimensions for the poster: 5 feet by 3 feet or 3 feet by 5 feet. Both sets of dimensions satisfy the given perimeter and area.
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