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Zad 2i 3
Proszę szybko


Zad 2i 3 Proszę Szybko class=

Odpowiedź :

We wszystkich zadaniach wykorzystujemy tw. Pitagorasa.

Zadanie 2.

a)

[tex]h^2+(\sqrt{7})^2=7^2\\ h^2+7=49\\ h^2=42\\ a^2+h^2=8^2\\ a^2+42=64\\ a^2=22\\ a=\sqrt{22}[/tex]

b)

[tex](b+3,8\sqrt{2})^2=(7+5)^2+(3\sqrt{2})^2\\ (b+3,8\sqrt{2})^2=144+18=162\\ b+3,8\sqrt{2}=\sqrt{162}=\sqrt{81*2}=9\sqrt{2}\\ b=9\sqrt{2}-3,8\sqrt{2}=5,2\sqrt{2}[/tex]

Zadanie 3.

a)

[tex]a=6\\ \frac{1}{2} e=3\sqrt{3}\\ e=6\sqrt{3}\\ (\frac{1}{2} f)^2+(\frac{1}{2} e)^2=6^2\\ (\frac{1}{2} f)^2+(3\sqrt{3})^2=6^2\\ (\frac{1}{2} f)^2+27=36\\ (\frac{1}{2} f)^2=9\\ \frac{1}{2} f=3\\ f=6\\ P=\frac{e*f}{2} =\frac{6\sqrt{3}*6}{2}=18\sqrt{3}\\ Obw=4a=4*6=24[/tex]

b)

[tex]h^2+15^2=17^2\\ h^2+225=289\\ h^2=64\\ h=8\\ a=15+10+15=40\\ P=\frac{(a+b)*h}{2}=\frac{(40+10)*8}{2}=200\\ Obw=a+b+2c=40+10+2*17=84[/tex]