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Mathematics

1 answer:

guajiro [1.7K]3 years ago

8 0

Step-by-step explanation:

SA=ph+2A, that is, perimeter × height+ twice area

p=21+20+29=70cm

h=22cm

70×22=1540cm

A=1/2 ×20×21=210×2=420

1540+420=1960cm2

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