[tex]\large\text{Hello there! :)}[/tex]
[tex]\text{Formula for the perimeter: P = 6x + 12}\\\\\text{Dimensions: l = 21, w = 15}\\\\\text{Verification below.}[/tex]
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[tex]\text{Begin by writing an equation for the perimeter of the rectangle.}\\\\\text{Formula: P = 2l + 2w}\\\\P = 2(2x + 1) + 2(x + 5)\\\\P = 4x + 2 + 2x + 10\\\\\text{Combine like terms:}\\\\\boxed{P = 6x + 12}\\\\\text{Solve for the dimensions:}\\\\72 = 6x + 12\\\\\text{Subtract 12 from both sides:}\\\\60 = 6x\\\\\text{Divide both sides by 6:}\\\\x = 10\\\\\text{Substitute in 10 for x in the equations for each side length:}\\\\l = 2x + 1\\\\l = 2(10) + 1\\\\\boxed{l = 20 + 1 = 21units}[/tex]
[tex]w = (10) + 5\\\\\boxed{w = 15 units}[/tex]
[tex]\text{Use the formula for the area of a rectangle to verify. A = l * w:}\\\\\boxed{A = 15 * 21 = 315 units^{2} }[/tex]
