A = (hb) / 2.......2A = hb.....(2A) / h = b
A = 54
h = 9
2(54) / 9 = b
108/9 = b
12 = b.....so the base (b) is 12 m
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A = bh
A = 1440
h = 32
1440 = 32b
1440/32 = b
45 = b....so the base is 45 in
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sorry...dont know the last one
