Whakaoti i te {l}{x+y=2}{2x+4y=8}

$$\left. \begin{array} { l } { x + y = 2 } \\ { 2 x + 4 y = 8 } \end{array} \right.$$

Whakaoti mō x, y

$$x=0$$

$$y=2$$

Ngā Upane e Whakamahi ana i te Whakakapinga

Hei whakaoti i ētahi whārite takirua mā te whakakapinga, me whakaoti tētahi whārite i te tuatahi mō tētahi o ngā taurangi. Ka whakakapi i te otinga mō taua taurangi ki tērā o ngā whārite.

$$x+y=2,2x+4y=8$$

Kōwhiria tētahi o ngā whārite ka whakaotia mō te x mā te wehe i te x i te taha mauī o te tohu ōrite.

$$x+y=2$$

Me tango y mai i ngā taha e rua o te whārite.

$$x=-y+2$$

Whakakapia te -y+2 mō te x ki tērā atu whārite, 2x+4y=8.

$$2\left(-y+2\right)+4y=8$$

Whakareatia 2 ki te -y+2.

$$-2y+4+4y=8$$

Tāpiri -2y ki te 4y.

$$2y+4=8$$

Me tango 4 mai i ngā taha e rua o te whārite.

$$2y=4$$

Whakawehea ngā taha e rua ki te 2.

$$y=2$$

Whakaurua te 2 mō y ki x=-y+2. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$x=-2+2$$

Tāpiri 2 ki te -2.

$$x=0$$

Kua oti te pūnaha te whakatau.

$$x=0,y=2$$

Ngā Upane e Whakamahi ana i Ngā Poukapa

Tuhia ngā whārite ki te tānga ngahuru ka whakamahi i ngā poukapa hei whakaoti i te pūnaha o ngā whārite.

$$x+y=2,2x+4y=8$$

Tuhia ngā whārite ki te tikanga tātai poukapa.

$$\left(\begin{matrix}1&1\\2&4\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}2\\8\end{matrix}\right)$$

Whakarea mauī i te whārite ki te poukapa kōaro o \left(\begin{matrix}1&1\\2&4\end{matrix}\right).

$$inverse(\left(\begin{matrix}1&1\\2&4\end{matrix}\right))\left(\begin{matrix}1&1\\2&4\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\2&4\end{matrix}\right))\left(\begin{matrix}2\\8\end{matrix}\right)$$

Ko te hua o tētahi poukapa me te kōaro ko te poukapa tuakiri.

$$\left(\begin{matrix}1&0\\0&1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\2&4\end{matrix}\right))\left(\begin{matrix}2\\8\end{matrix}\right)$$

Whakareatia ngā poukapa kei te taha mauī o te tohu ōrite.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\2&4\end{matrix}\right))\left(\begin{matrix}2\\8\end{matrix}\right)$$

Mō te poukapa 2\times 2 \left(\begin{matrix}a&b\\c&d\end{matrix}\right), ko te poukapa kōaro ko \left(\begin{matrix}\frac{d}{ad-bc}&\frac{-b}{ad-bc}\\\frac{-c}{ad-bc}&\frac{a}{ad-bc}\end{matrix}\right), kia tuhia anō ai te whārite poukapa hei rapanga whakarea poukapa.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{4}{4-2}&-\frac{1}{4-2}\\-\frac{2}{4-2}&\frac{1}{4-2}\end{matrix}\right)\left(\begin{matrix}2\\8\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}2&-\frac{1}{2}\\-1&\frac{1}{2}\end{matrix}\right)\left(\begin{matrix}2\\8\end{matrix}\right)$$

Whakareatia ngā poukapa.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}2\times 2-\frac{1}{2}\times 8\\-2+\frac{1}{2}\times 8\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}0\\2\end{matrix}\right)$$

Tangohia ngā huānga poukapa x me y.

$$x=0,y=2$$

Ngā Upane e Whakamahi i te Tangohanga

Hei whakaoti mā te tangohanga, ko ngā tau whakarea o tētahi o ngā taurangi me mātua ōrite i ngā whārite e rua kia whakakorehia ai te taurangi ina tangohia tētahi whārite mai i tētahi atu.

$$x+y=2,2x+4y=8$$

Kia ōrite ai a x me 2x, whakareatia ngā kīanga tau katoa kei ia taha o te whārite tuatahi ki te 2 me ngā kīanga tau katoa kei ia taha o te whārite tuarua ki te 1.

$$2x+2y=2\times 2,2x+4y=8$$

Whakarūnātia.

$$2x+2y=4,2x+4y=8$$

Me tango 2x+4y=8 mai i 2x+2y=4 mā te tango i ngā kīanga tau ōrite i ia taha o te tohu ōrite.

$$2x-2x+2y-4y=4-8$$

Tāpiri 2x ki te -2x. Ka whakakore atu ngā kupu 2x me -2x, ka toe he whārite me tētahi taurangi kotahi ka taea te whakaoti.

$$2y-4y=4-8$$

Tāpiri 2y ki te -4y.

$$-2y=4-8$$

Tāpiri 4 ki te -8.

$$-2y=-4$$

Whakawehea ngā taha e rua ki te -2.

$$y=2$$

Whakaurua te 2 mō y ki 2x+4y=8. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$2x+4\times 2=8$$

Whakareatia 4 ki te 2.

$$2x+8=8$$

Me tango 8 mai i ngā taha e rua o te whārite.

$$2x=0$$

Whakawehea ngā taha e rua ki te 2.

$$x=0$$

Kua oti te pūnaha te whakatau.

$$x=0,y=2$$