how do u solve problems like this ?
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The first and second polygons are exactly the same, the only difference is that the second is bigger! If we look right the first polygon is 4 cm and the second is triple which means that we will have to triple the area of the First polygon to discover the area of the second polygon!
if the first polygon is 4 cm long and the second 12 cm means that the second polygon has three times the area of the first polygon!
[tex](4 cm.3=12 cm)\\A-10 cm^{2}.3=30 cm^{2}[/tex]
the second polygon has [tex]30 cm^{2}[/tex] of area
[tex]A=30 cm^{2}[/tex]