Whakaoti i te {l}{2x+y=11}{3x-y=9}

$$\left. \begin{array} { l } { 2 x + y = 11 } \\ { 3 x - y = 9 } \end{array} \right.$$

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.

$$2x+y=11,3x-y=9$$

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

$$2x+y=11$$

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

$$2x=-y+11$$

Whakawehea ngā taha e rua ki te 2.

$$x=\frac{1}{2}\left(-y+11\right)$$

Whakareatia \frac{1}{2} ki te -y+11.

$$x=-\frac{1}{2}y+\frac{11}{2}$$

Whakakapia te \frac{-y+11}{2} mō te x ki tērā atu whārite, 3x-y=9.

$$3\left(-\frac{1}{2}y+\frac{11}{2}\right)-y=9$$

Whakareatia 3 ki te \frac{-y+11}{2}.

$$-\frac{3}{2}y+\frac{33}{2}-y=9$$

Tāpiri -\frac{3y}{2} ki te -y.

$$-\frac{5}{2}y+\frac{33}{2}=9$$

Me tango \frac{33}{2} mai i ngā taha e rua o te whārite.

$$-\frac{5}{2}y=-\frac{15}{2}$$

Whakawehea ngā taha e rua o te whārite ki te -\frac{5}{2}, he ōrite ki te whakarea i ngā taha e rua ki te tau huripoki o te hautanga.

$$y=3$$

Whakaurua te 3 mō y ki x=-\frac{1}{2}y+\frac{11}{2}. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$x=-\frac{1}{2}\times 3+\frac{11}{2}$$

Whakareatia -\frac{1}{2} ki te 3.

$$x=\frac{-3+11}{2}$$

Tāpiri \frac{11}{2} ki te -\frac{3}{2} 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.

$$x=4$$

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.

$$2x+y=11,3x-y=9$$

Tuhia ngā whārite ki te tikanga tātai poukapa.

$$\left(\begin{matrix}2&1\\3&-1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}11\\9\end{matrix}\right)$$

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

$$inverse(\left(\begin{matrix}2&1\\3&-1\end{matrix}\right))\left(\begin{matrix}2&1\\3&-1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}2&1\\3&-1\end{matrix}\right))\left(\begin{matrix}11\\9\end{matrix}\right)$$

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

$$\left(\begin{matrix}1&0\\0&1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}2&1\\3&-1\end{matrix}\right))\left(\begin{matrix}11\\9\end{matrix}\right)$$

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

$$\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}2&1\\3&-1\end{matrix}\right))\left(\begin{matrix}11\\9\end{matrix}\right)$$

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.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}-\frac{1}{2\left(-1\right)-3}&-\frac{1}{2\left(-1\right)-3}\\-\frac{3}{2\left(-1\right)-3}&\frac{2}{2\left(-1\right)-3}\end{matrix}\right)\left(\begin{matrix}11\\9\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{1}{5}&\frac{1}{5}\\\frac{3}{5}&-\frac{2}{5}\end{matrix}\right)\left(\begin{matrix}11\\9\end{matrix}\right)$$

Whakareatia ngā poukapa.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{1}{5}\times 11+\frac{1}{5}\times 9\\\frac{3}{5}\times 11-\frac{2}{5}\times 9\end{matrix}\right)$$

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.

$$2x+y=11,3x-y=9$$

Kia ōrite ai a 2x me 3x, whakareatia ngā kīanga tau katoa kei ia taha o te whārite tuatahi ki te 3 me ngā kīanga tau katoa kei ia taha o te whārite tuarua ki te 2.

$$3\times 2x+3y=3\times 11,2\times 3x+2\left(-1\right)y=2\times 9$$

Whakarūnātia.

$$6x+3y=33,6x-2y=18$$

Me tango 6x-2y=18 mai i 6x+3y=33 mā te tango i ngā kīanga tau ōrite i ia taha o te tohu ōrite.

$$6x-6x+3y+2y=33-18$$

Tāpiri 6x ki te -6x. Ka whakakore atu ngā kupu 6x me -6x, ka toe he whārite me tētahi taurangi kotahi ka taea te whakaoti.

$$3y+2y=33-18$$

Tāpiri 3y ki te 2y.

$$5y=33-18$$

Tāpiri 33 ki te -18.

$$5y=15$$

Whakawehea ngā taha e rua ki te 5.

$$y=3$$

Whakaurua te 3 mō y ki 3x-y=9. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$3x-3=9$$

Me tāpiri 3 ki ngā taha e rua o te whārite.

$$3x=12$$

Whakawehea ngā taha e rua ki te 3.

$$x=4$$

Kua oti te pūnaha te whakatau.

$$x=4,y=3$$