Whakaoti i te x+2y=-1;2x-3y=12

$$x + 2 y = - 1 ; 2 x - 3 y = 12$$

Whakaoti mō x, y

$$x=3$$

$$y=-2$$

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.

$$x+2y=-1,2x-3y=12$$

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

$$x+2y=-1$$

Me tango 2y mai i ngā taha e rua o te whārite.

$$x=-2y-1$$

Whakakapia te -2y-1 mō te x ki tērā atu whārite, 2x-3y=12.

$$2\left(-2y-1\right)-3y=12$$

Whakareatia 2 ki te -2y-1.

$$-4y-2-3y=12$$

Tāpiri -4y ki te -3y.

$$-7y-2=12$$

Me tāpiri 2 ki ngā taha e rua o te whārite.

$$-7y=14$$

Whakawehea ngā taha e rua ki te -7.

$$y=-2$$

Whakaurua te -2 mō y ki x=-2y-1. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$x=-2\left(-2\right)-1$$

Whakareatia -2 ki te -2.

$$x=4-1$$

Tāpiri -1 ki te 4.

$$x=3$$

Kua oti te pūnaha te whakatau.

$$x=3,y=-2$$

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.

$$x+2y=-1,2x-3y=12$$

Tuhia ngā whārite ki te tikanga tātai poukapa.

$$\left(\begin{matrix}1&2\\2&-3\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}-1\\12\end{matrix}\right)$$

Whakarea mauī i te whārite ki te poukapa kōaro o \left(\begin{matrix}1&2\\2&-3\end{matrix}\right).

$$inverse(\left(\begin{matrix}1&2\\2&-3\end{matrix}\right))\left(\begin{matrix}1&2\\2&-3\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&2\\2&-3\end{matrix}\right))\left(\begin{matrix}-1\\12\end{matrix}\right)$$

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

$$\left(\begin{matrix}1&0\\0&1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&2\\2&-3\end{matrix}\right))\left(\begin{matrix}-1\\12\end{matrix}\right)$$

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

$$\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&2\\2&-3\end{matrix}\right))\left(\begin{matrix}-1\\12\end{matrix}\right)$$

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

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}-\frac{3}{-3-2\times 2}&-\frac{2}{-3-2\times 2}\\-\frac{2}{-3-2\times 2}&\frac{1}{-3-2\times 2}\end{matrix}\right)\left(\begin{matrix}-1\\12\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{3}{7}&\frac{2}{7}\\\frac{2}{7}&-\frac{1}{7}\end{matrix}\right)\left(\begin{matrix}-1\\12\end{matrix}\right)$$

Whakareatia ngā poukapa.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{3}{7}\left(-1\right)+\frac{2}{7}\times 12\\\frac{2}{7}\left(-1\right)-\frac{1}{7}\times 12\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}3\\-2\end{matrix}\right)$$

Tangohia ngā huānga poukapa x me y.

$$x=3,y=-2$$

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.

$$x+2y=-1,2x-3y=12$$

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.

$$2x+2\times 2y=2\left(-1\right),2x-3y=12$$

Whakarūnātia.

$$2x+4y=-2,2x-3y=12$$

Me tango 2x-3y=12 mai i 2x+4y=-2 mā te tango i ngā kīanga tau ōrite i ia taha o te tohu ōrite.

$$2x-2x+4y+3y=-2-12$$

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.

$$4y+3y=-2-12$$

Tāpiri 4y ki te 3y.

$$7y=-2-12$$

Tāpiri -2 ki te -12.

$$7y=-14$$

Whakawehea ngā taha e rua ki te 7.

$$y=-2$$

Whakaurua te -2 mō y ki 2x-3y=12. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$2x-3\left(-2\right)=12$$

Whakareatia -3 ki te -2.

$$2x+6=12$$

Me tango 6 mai i ngā taha e rua o te whārite.

$$2x=6$$

Whakawehea ngā taha e rua ki te 2.

$$x=3$$

Kua oti te pūnaha te whakatau.

$$x=3,y=-2$$