The diagonal of a rectangle is 8m longer than its shorter side. If the area of the rectangle is 60 sq.m, find its dimensions. Answer: The dimensions of the rectangle are 5 and 12 meters. Step-by-step explanation: Shorter side (Width): x Diagonal: x + 8 Longer side: a Use the Pythagorean theorem to find the longer side a: c² = a² + b² Where: c = diagonal (x+8) b = shorter side/width (x) a = longer side/length (x+8)² = a² + (x)² a² = (x+8)² - x² a² = x² + 16x + 64 - x² a² = 16x + 64 a² = 16(x + 4) √a² = √16 (x+4) a = 4 √(x+4) The longer side is 4√(x+4) m. Find the dimension of the rectangle when the area is 60 m²: Area = (length) (Width) 60 = (4√(x+4) (x) 60 = 4x√(x+4) 4x√(x+4)² = (60)² 16x²(x+4) = 3,600 16x³ + 64x² - 3600 = 0 16x³ + 64x² - 3600/16 = 0 x³ + 4x²- 225 = 0 Find the roots or x: Rational theorem for polynomial roots: Factors of 225: (±)1,3, 5 ,9,15,25,45,75,225 Trial: 5 Divide by x - 5: (x³ + 4x²- 225) / (x-5) = x² + 9x + 45 Therefore, x = 5 Find the roots of x² + ...
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