Whakaoti i te {l}{x+y=4}{4x-3y=-19}

$$\left\{ \begin{array} { l } { x + y = 4 } \\ { 4 x - 3 y = - 19 } \end{array} \right.$$

Whakaoti mō x, y

$$x=-1$$

$$y=5$$

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.

$$x+y=4,4x-3y=-19$$

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

$$x+y=4$$

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

$$x=-y+4$$

Whakakapia te -y+4 mō te x ki tērā atu whārite, 4x-3y=-19.

$$4\left(-y+4\right)-3y=-19$$

Whakareatia 4 ki te -y+4.

$$-4y+16-3y=-19$$

Tāpiri -4y ki te -3y.

$$-7y+16=-19$$

Me tango 16 mai i ngā taha e rua o te whārite.

$$-7y=-35$$

Whakawehea ngā taha e rua ki te -7.

$$y=5$$

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

$$x=-5+4$$

Tāpiri 4 ki te -5.

$$x=-1$$

Kua oti te pūnaha te whakatau.

$$x=-1,y=5$$

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.

$$x+y=4,4x-3y=-19$$

Tuhia ngā whārite ki te tikanga tātai poukapa.

$$\left(\begin{matrix}1&1\\4&-3\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}4\\-19\end{matrix}\right)$$

Whakarea mauī i te whārite ki te poukapa kōaro o \left(\begin{matrix}1&1\\4&-3\end{matrix}\right).

$$inverse(\left(\begin{matrix}1&1\\4&-3\end{matrix}\right))\left(\begin{matrix}1&1\\4&-3\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\4&-3\end{matrix}\right))\left(\begin{matrix}4\\-19\end{matrix}\right)$$

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

$$\left(\begin{matrix}1&0\\0&1\end{matrix}\right)\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\4&-3\end{matrix}\right))\left(\begin{matrix}4\\-19\end{matrix}\right)$$

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

$$\left(\begin{matrix}x\\y\end{matrix}\right)=inverse(\left(\begin{matrix}1&1\\4&-3\end{matrix}\right))\left(\begin{matrix}4\\-19\end{matrix}\right)$$

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.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}-\frac{3}{-3-4}&-\frac{1}{-3-4}\\-\frac{4}{-3-4}&\frac{1}{-3-4}\end{matrix}\right)\left(\begin{matrix}4\\-19\end{matrix}\right)$$

Mahia ngā tātaitanga.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{3}{7}&\frac{1}{7}\\\frac{4}{7}&-\frac{1}{7}\end{matrix}\right)\left(\begin{matrix}4\\-19\end{matrix}\right)$$

Whakareatia ngā poukapa.

$$\left(\begin{matrix}x\\y\end{matrix}\right)=\left(\begin{matrix}\frac{3}{7}\times 4+\frac{1}{7}\left(-19\right)\\\frac{4}{7}\times 4-\frac{1}{7}\left(-19\right)\end{matrix}\right)$$

Mahia ngā tātaitanga.

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

Tangohia ngā huānga poukapa x me y.

$$x=-1,y=5$$

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.

$$x+y=4,4x-3y=-19$$

Kia ōrite ai a x me 4x, whakareatia ngā kīanga tau katoa kei ia taha o te whārite tuatahi ki te 4 me ngā kīanga tau katoa kei ia taha o te whārite tuarua ki te 1.

$$4x+4y=4\times 4,4x-3y=-19$$

Whakarūnātia.

$$4x+4y=16,4x-3y=-19$$

Me tango 4x-3y=-19 mai i 4x+4y=16 mā te tango i ngā kīanga tau ōrite i ia taha o te tohu ōrite.

$$4x-4x+4y+3y=16+19$$

Tāpiri 4x ki te -4x. Ka whakakore atu ngā kupu 4x me -4x, ka toe he whārite me tētahi taurangi kotahi ka taea te whakaoti.

$$4y+3y=16+19$$

Tāpiri 4y ki te 3y.

$$7y=16+19$$

Tāpiri 16 ki te 19.

$$7y=35$$

Whakawehea ngā taha e rua ki te 7.

$$y=5$$

Whakaurua te 5 mō y ki 4x-3y=-19. I te mea kotahi anake te taurangi kei te whārite i puta, ka taea e koe te whakaoti mō x hāngai tonu.

$$4x-3\times 5=-19$$

Whakareatia -3 ki te 5.

$$4x-15=-19$$

Me tāpiri 15 ki ngā taha e rua o te whārite.

$$4x=-4$$

Whakawehea ngā taha e rua ki te 4.

$$x=-1$$

Kua oti te pūnaha te whakatau.

$$x=-1,y=5$$