Answer: [tex]20-\frac{1}{4}x+\frac{4}{3}y[/tex]
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Work Shown:
[tex]P = 2L + 2W\\\\P = 2\left(10-x+\frac{4}{9}y\right) + 2\left(\frac{7}{8}x+\frac{2}{9}y\right)\\\\P = 2\left(10\right)-2x+2\left(\frac{4}{9}y\right) + 2\left(\frac{7}{8}x\right)+2\left(\frac{2}{9}y\right)\\\\[/tex]
[tex]P = 20-2x+\frac{8}{9}y + \frac{14}{8}x+\frac{4}{9}y\\\\P = 20-2x+\frac{8}{9}y + \frac{7}{4}x+\frac{4}{9}y\\\\P = 20+\left(-2x + \frac{7}{4}x\right)+\left(\frac{8}{9}y+\frac{4}{9}y\right)\\\\[/tex]
[tex]P = 20+\left(-\frac{8}{4}x + \frac{7}{4}x\right)+\left(\frac{8}{9}y+\frac{4}{9}y\right)\\\\P = 20+\left(\frac{-8+7}{4}x\right)+\left(\frac{8+4}{9}y\right)\\\\P = 20-\frac{1}{4}x+\frac{12}{9}y\\\\P = 20-\frac{1}{4}x+\frac{4}{3}y\\\\[/tex]
