koło w rombie
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koło w rombie
2x,2y -przekątne
\(\displaystyle{ 2x+2y=14}\)
\(\displaystyle{ x+y=7}\)
\(\displaystyle{ x=7-y}\)
\(\displaystyle{ x ^{2} +y ^{2} =a ^{2}}\)
\(\displaystyle{ 49-14y+y ^{2} +y ^{2} =25}\)
\(\displaystyle{ 2y ^{2} -14y+24=0}\)
\(\displaystyle{ \Delta=196-192=4}\)
\(\displaystyle{ \sqrt{\Delta}=2}\)
\(\displaystyle{ y _{1}= \frac{14-2}{4}=3}\) LUB \(\displaystyle{ y _{2}= \frac{14+2}{4}=4}\)
\(\displaystyle{ x=4}\) LUB \(\displaystyle{ x=3}\)
\(\displaystyle{ P= \frac{1}{2} 2x 2y=24}\)
\(\displaystyle{ P=ah}\)
\(\displaystyle{ 24=5h}\)
\(\displaystyle{ h= \frac{24}{5}}\)
\(\displaystyle{ r=0,5h}\)
\(\displaystyle{ r=2,4}\)
\(\displaystyle{ Po=\pi r ^{2} =5,76 \pi}\)
\(\displaystyle{ 2x+2y=14}\)
\(\displaystyle{ x+y=7}\)
\(\displaystyle{ x=7-y}\)
\(\displaystyle{ x ^{2} +y ^{2} =a ^{2}}\)
\(\displaystyle{ 49-14y+y ^{2} +y ^{2} =25}\)
\(\displaystyle{ 2y ^{2} -14y+24=0}\)
\(\displaystyle{ \Delta=196-192=4}\)
\(\displaystyle{ \sqrt{\Delta}=2}\)
\(\displaystyle{ y _{1}= \frac{14-2}{4}=3}\) LUB \(\displaystyle{ y _{2}= \frac{14+2}{4}=4}\)
\(\displaystyle{ x=4}\) LUB \(\displaystyle{ x=3}\)
\(\displaystyle{ P= \frac{1}{2} 2x 2y=24}\)
\(\displaystyle{ P=ah}\)
\(\displaystyle{ 24=5h}\)
\(\displaystyle{ h= \frac{24}{5}}\)
\(\displaystyle{ r=0,5h}\)
\(\displaystyle{ r=2,4}\)
\(\displaystyle{ Po=\pi r ^{2} =5,76 \pi}\)