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The perimeter of a chalkboard is 1818 feet. The area is 1818 square feet. What are the dimensions of the board?\newline___\_\_\_ feet by ___\_\_\_ feet

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Q. The perimeter of a chalkboard is 1818 feet. The area is 1818 square feet. What are the dimensions of the board?\newline___\_\_\_ feet by ___\_\_\_ feet
  1. Perimeter Equation: Let's denote the length of the chalkboard as LL and the width as WW. The perimeter (PP) of a rectangle is given by the formula P=2(L+W)P = 2(L + W). We are given that the perimeter is 1818 feet, so we have:\newline2(L+W)=182(L + W) = 18
  2. Isolating Variables: To find the length and width, we need to divide both sides of the perimeter equation by 22 to isolate the L+WL + W term:\newlineL+W=182L + W = \frac{18}{2}\newlineL+W=9L + W = 9
  3. Area Equation: The area AA of a rectangle is given by the formula A=L×WA = L \times W. We are given that the area is 1818 square feet, so we have:\newlineL×W=18L \times W = 18
  4. System of Equations: Now we have a system of two equations with two variables:\newline11) L+W=9L + W = 9\newline22) L×W=18L \times W = 18\newlineWe can solve this system by substitution or elimination. Let's try substitution. If we solve the first equation for WW, we get:\newlineW=9LW = 9 - L
  5. Substitution: Substitute W=9LW = 9 - L into the second equation L×W=18L \times W = 18:L×(9L)=18L \times (9 - L) = 18Expanding this, we get:9LL2=189L - L^2 = 18
  6. Quadratic Equation: Rearrange the equation to form a quadratic equation: L29L+18=0L^2 - 9L + 18 = 0
  7. Factoring: We can factor this quadratic equation: \newline(L3)(L6)=0(L - 3)(L - 6) = 0
  8. Solving for L: Setting each factor equal to zero gives us the possible values for L:\newlineL3=0L - 3 = 0 or L6=0L - 6 = 0\newlineSo, L=3L = 3 or L=6L = 6
  9. Checking Solutions: If L=3L = 3, then W=9L=93=6W = 9 - L = 9 - 3 = 6. If L=6L = 6, then W=9L=96=3W = 9 - L = 9 - 6 = 3. Both pairs (L=3,W=6)(L = 3, W = 6) and (L=6,W=3)(L = 6, W = 3) satisfy the system of equations, so the dimensions of the chalkboard can be 33 feet by 66 feet or 66 feet by 33 feet.

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