The perimeter is the sum of all the sides of the figure⇒
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[tex]P=a+b+c+d...[/tex]
[tex]P=(y+9)+(3y+3)+(4y+6)=y+9+3y+3+4y+6=8y+18[/tex]
152
[tex]P=a+b+c+d...\\P=(4a-100)+(2a-15)+(2a+40)=4a-100+2a-15+2a+40=\\=8a-75[/tex]
153
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