Whakaoti i te {l}{5x-y=13}{2x+3y=12}

$$\left. \begin{array} { l } { 5 x - y = 13 } \\ { 2 x + 3 y = 12 } \end{array} \right.$$

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.

$$5x-y=13,2x+3y=12$$

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

$$5x-y=13$$

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

$$5x=y+13$$

Whakawehea ngā taha e rua ki te 5.

$$x=\frac{1}{5}\left(y+13\right)$$

Whakareatia \frac{1}{5} ki te y+13.

$$x=\frac{1}{5}y+\frac{13}{5}$$

Whakakapia te \frac{13+y}{5} mō te x ki tērā atu whārite, 2x+3y=12.

$$2\left(\frac{1}{5}y+\frac{13}{5}\right)+3y=12$$

Whakareatia 2 ki te \frac{13+y}{5}.

$$\frac{2}{5}y+\frac{26}{5}+3y=12$$

Tāpiri \frac{2y}{5} ki te 3y.

$$\frac{17}{5}y+\frac{26}{5}=12$$

Me tango \frac{26}{5} mai i ngā taha e rua o te whārite.

$$\frac{17}{5}y=\frac{34}{5}$$

Whakawehea ngā taha e rua o te whārite ki te \frac{17}{5}, he ōrite ki te whakarea i ngā taha e rua ki te tau huripoki o te hautanga.

$$y=2$$

Whakaurua te 2 mō y ki x=\frac{1}{5}y+\frac{13}{5}. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$x=\frac{1}{5}\times 2+\frac{13}{5}$$

Whakareatia \frac{1}{5} ki te 2.

$$x=\frac{2+13}{5}$$

Tāpiri \frac{13}{5} ki te \frac{2}{5} mā te kimi i te tauraro pātahi me te tāpiri i ngā taurunga. Ka whakaiti i te hautanga ki ngā kīanga tau iti rawa e taea ana.

$$x=3$$

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.

$$5x-y=13,2x+3y=12$$

Tuhia ngā whārite ki te tikanga tātai poukapa.

$$\left(\begin{matrix}5&-1\\2&3\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}13\\12\end{matrix}\right)$$

Whakarea mauī i te whārite ki te poukapa kōaro o \left(\begin{matrix}5&-1\\2&3\end{matrix}\right).

$$inverse(\left(\begin{matrix}5&-1\\2&3\end{matrix}\right))\left(\begin{matrix}5&-1\\2&3\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}5&-1\\2&3\end{matrix}\right))\left(\begin{matrix}13\\12\end{matrix}\right)$$

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

$$\left(\begin{matrix}1&0\\0&1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}5&-1\\2&3\end{matrix}\right))\left(\begin{matrix}13\\12\end{matrix}\right)$$

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

$$\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}5&-1\\2&3\end{matrix}\right))\left(\begin{matrix}13\\12\end{matrix}\right)$$

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.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{3}{5\times 3-\left(-2\right)}&-\frac{-1}{5\times 3-\left(-2\right)}\\-\frac{2}{5\times 3-\left(-2\right)}&\frac{5}{5\times 3-\left(-2\right)}\end{matrix}\right)\left(\begin{matrix}13\\12\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{3}{17}&\frac{1}{17}\\-\frac{2}{17}&\frac{5}{17}\end{matrix}\right)\left(\begin{matrix}13\\12\end{matrix}\right)$$

Whakareatia ngā poukapa.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{3}{17}\times 13+\frac{1}{17}\times 12\\-\frac{2}{17}\times 13+\frac{5}{17}\times 12\end{matrix}\right)$$

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.

$$5x-y=13,2x+3y=12$$

Kia ōrite ai a 5x 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 5.

$$2\times 5x+2\left(-1\right)y=2\times 13,5\times 2x+5\times 3y=5\times 12$$

Whakarūnātia.

$$10x-2y=26,10x+15y=60$$

Me tango 10x+15y=60 mai i 10x-2y=26 mā te tango i ngā kīanga tau ōrite i ia taha o te tohu ōrite.

$$10x-10x-2y-15y=26-60$$

Tāpiri 10x ki te -10x. Ka whakakore atu ngā kupu 10x me -10x, ka toe he whārite me tētahi taurangi kotahi ka taea te whakaoti.

$$-2y-15y=26-60$$

Tāpiri -2y ki te -15y.

$$-17y=26-60$$

Tāpiri 26 ki te -60.

$$-17y=-34$$

Whakawehea ngā taha e rua ki te -17.

$$y=2$$

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.

$$2x+3\times 2=12$$

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.

$$x=3,y=2$$