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1)
Area $A= \dfrac{(B+b)×h}{2} = \dfrac{(9+6)×5}{2} = \dfrac{15×5}{2} = 37,5\,cm^2.$
2)
Altezza $h= \dfrac{2A}{B+b} = \dfrac{2×105}{24+11} = \dfrac{210}{35} = 6\,cm.$
3)
Base maggiore $B= \dfrac{2A}{h}-b = \dfrac{2×175}{10}-15 = \dfrac{350}{10}-15 = 20\,cm.$
4)
Base minore $b= \dfrac{2A}{h}-B = \dfrac{2×26}{4}-7,5 = \dfrac{52}{4}-7,5 = 5,5\,cm.$