Whakaoti i te {l}{x+y=7}{5x+12y=7}

$$\left. \begin{array} { l } { x + y = 7 } \\ { 5 x + 12 y = 7 } \end{array} \right.$$

Whakaoti mō x, y

$$x=11$$

$$y=-4$$

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.

$$x+y=7,5x+12y=7$$

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

$$x+y=7$$

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

$$x=-y+7$$

Whakakapia te -y+7 mō te x ki tērā atu whārite, 5x+12y=7.

$$5\left(-y+7\right)+12y=7$$

Whakareatia 5 ki te -y+7.

$$-5y+35+12y=7$$

Tāpiri -5y ki te 12y.

$$7y+35=7$$

Me tango 35 mai i ngā taha e rua o te whārite.

$$7y=-28$$

Whakawehea ngā taha e rua ki te 7.

$$y=-4$$

Whakaurua te -4 mō y ki x=-y+7. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$x=-\left(-4\right)+7$$

Whakareatia -1 ki te -4.

$$x=4+7$$

Tāpiri 7 ki te 4.

$$x=11$$

Kua oti te pūnaha te whakatau.

$$x=11,y=-4$$

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.

$$x+y=7,5x+12y=7$$

Tuhia ngā whārite ki te tikanga tātai poukapa.

$$\left(\begin{matrix}1&1\\5&12\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}7\\7\end{matrix}\right)$$

Whakarea mauī i te whārite ki te poukapa kōaro o \left(\begin{matrix}1&1\\5&12\end{matrix}\right).

$$inverse(\left(\begin{matrix}1&1\\5&12\end{matrix}\right))\left(\begin{matrix}1&1\\5&12\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\5&12\end{matrix}\right))\left(\begin{matrix}7\\7\end{matrix}\right)$$

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

$$\left(\begin{matrix}1&0\\0&1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\5&12\end{matrix}\right))\left(\begin{matrix}7\\7\end{matrix}\right)$$

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

$$\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\5&12\end{matrix}\right))\left(\begin{matrix}7\\7\end{matrix}\right)$$

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.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{12}{12-5}&-\frac{1}{12-5}\\-\frac{5}{12-5}&\frac{1}{12-5}\end{matrix}\right)\left(\begin{matrix}7\\7\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{12}{7}&-\frac{1}{7}\\-\frac{5}{7}&\frac{1}{7}\end{matrix}\right)\left(\begin{matrix}7\\7\end{matrix}\right)$$

Whakareatia ngā poukapa.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{12}{7}\times 7-\frac{1}{7}\times 7\\-\frac{5}{7}\times 7+\frac{1}{7}\times 7\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}11\\-4\end{matrix}\right)$$

Tangohia ngā huānga poukapa x me y.

$$x=11,y=-4$$

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.

$$x+y=7,5x+12y=7$$

Kia ōrite ai a x me 5x, whakareatia ngā kīanga tau katoa kei ia taha o te whārite tuatahi ki te 5 me ngā kīanga tau katoa kei ia taha o te whārite tuarua ki te 1.

$$5x+5y=5\times 7,5x+12y=7$$

Whakarūnātia.

$$5x+5y=35,5x+12y=7$$

Me tango 5x+12y=7 mai i 5x+5y=35 mā te tango i ngā kīanga tau ōrite i ia taha o te tohu ōrite.

$$5x-5x+5y-12y=35-7$$

Tāpiri 5x ki te -5x. Ka whakakore atu ngā kupu 5x me -5x, ka toe he whārite me tētahi taurangi kotahi ka taea te whakaoti.

$$5y-12y=35-7$$

Tāpiri 5y ki te -12y.

$$-7y=35-7$$

Tāpiri 35 ki te -7.

$$-7y=28$$

Whakawehea ngā taha e rua ki te -7.

$$y=-4$$

Whakaurua te -4 mō y ki 5x+12y=7. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$5x+12\left(-4\right)=7$$

Whakareatia 12 ki te -4.

$$5x-48=7$$

Me tāpiri 48 ki ngā taha e rua o te whārite.

$$5x=55$$

Whakawehea ngā taha e rua ki te 5.

$$x=11$$

Kua oti te pūnaha te whakatau.

$$x=11,y=-4$$