Question 204103
Perimeter =210 =2l +2w,,,but  w=l-15,,,
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210 = 2l +2(l-15)
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210 =2l + 2l -30
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240 = 4l
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60 = l,,,,,w= l-15 =60-15 = 45
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check per=210= 2*60 +2*45 = 120 +90,,,,,,ok