Odpowiedź :
[tex]a = 12 \ cm\\b = 5 \ cm\\h = 4 \ cm\\\\P = \frac{a+b}{2}\cdot h\\\\P = \frac{12cm+5cm}{2}\cdot 4cm\\\\P = 17 \ cm \cdot 2 \ cm\\\\\boxed{P = 34 \ cm^{2}}[/tex]
[tex]a = 12 \ cm\\b = 5 \ cm\\h = 4 \ cm\\\\P = \frac{a+b}{2}\cdot h\\\\P = \frac{12cm+5cm}{2}\cdot 4cm\\\\P = 17 \ cm \cdot 2 \ cm\\\\\boxed{P = 34 \ cm^{2}}[/tex]