[tex]P = 7\frac{7}{8} \ cm^{2} = \frac{7\cdot8+7}{8} \ cm^{2} = \frac{23}{8} \ cm^{2}\\\\h = 6\frac{3}{4} \ cm=\frac{6\cdot4+3}{4} = \frac{27}{4} \ cm\\\\a = ?[/tex]
Korzystamy ze wzoru na pole trójkąta:
[tex]P = \frac{1}{2}ah \ \ \ |\cdot2\\\\ah = 2P \ \ \ |:h\\\\a = \frac{2P}{h}\\\\a = \frac{2\cdot\frac{63}{8} \ cm^{2}}{\frac{27}{4} \ cm} =\frac{\frac{63}{4}}{\frac{27}{4}} \ cm =\frac{63}{27} \ cm\\\\\boxed{a = \frac{7}{3} \ cm = 2\frac{1}{3} \ cm}[/tex]
