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

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

Whakaoti mō x, y

$$x=4$$

$$y=3$$

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.

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

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

$$x-4y=-8$$

Me tāpiri 4y ki ngā taha e rua o te whārite.

$$x=4y-8$$

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

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

Tāpiri 4y ki te -2y.

$$2y-8=-2$$

Me tāpiri 8 ki ngā taha e rua o te whārite.

$$2y=6$$

Whakawehea ngā taha e rua ki te 2.

$$y=3$$

Whakaurua te 3 mō y ki x=4y-8. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$x=4\times 3-8$$

Whakareatia 4 ki te 3.

$$x=12-8$$

Tāpiri -8 ki te 12.

$$x=4$$

Kua oti te pūnaha te whakatau.

$$x=4,y=3$$

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.

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

Tuhia ngā whārite ki te tikanga tātai poukapa.

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

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

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

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

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

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

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

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.

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

Mahia ngā tātaitanga.

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

Whakareatia ngā poukapa.

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

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}4\\3\end{matrix}\right)$$

Tangohia ngā huānga poukapa x me y.

$$x=4,y=3$$

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.

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

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

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

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

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

Tāpiri -4y ki te 2y.

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

Tāpiri -8 ki te 2.

$$-2y=-6$$

Whakawehea ngā taha e rua ki te -2.

$$y=3$$

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

$$x-2\times 3=-2$$

Whakareatia -2 ki te 3.

$$x-6=-2$$

Me tāpiri 6 ki ngā taha e rua o te whārite.

$$x=4$$

Kua oti te pūnaha te whakatau.

$$x=4,y=3$$