Solve the problems. A regular pentagon and an equilateral triangle have the same perimeter. The perimeter of the pentagon is 5 (3x + 2) inches. The perimeter of the triangle is 4 (x - 2) inches. What is the perimeter of each figure? A 12 inches B 20 inches C 36 inches D 40 inches

Answer :

[tex]5(\frac{1}{2}x+2)[/tex][tex]4(x-2)[/tex]

Start by finding the value of x by making both expressions equal

[tex]5\cdot(\frac{1}{2}x+2)=4(x-2)[/tex]

distribut 5 and 4 on their corresponding sides

[tex]\begin{gathered} \frac{5}{2}x+10=4x-8 \\ \end{gathered}[/tex]

let all xs' to one side and all constants to the other

[tex]\begin{gathered} \frac{5}{2}x-4x=-8-10 \\ \frac{-3}{2}x=-18 \end{gathered}[/tex]

solve x by dividing by -3 and multiplying by 2

[tex]\begin{gathered} x=-18\cdot(\frac{2}{-3}) \\ x=12 \end{gathered}[/tex]

after finding the value of x into either one of the equations

[tex]4(x-2)[/tex][tex]\begin{gathered} 4\cdot(12-2) \\ 4\cdot10 \\ 40 \end{gathered}[/tex]

the perimeter of each figure is 40 inches.

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