Whakaoti i te -x^2+81=0

$$- x ^ { 2 } + 81 = 0$$

Whakaoti mō x

$$x=9$$

$$x=-9$$

Ngā Upane mā te Kimi Pūtakerua

Tangohia te 81 mai i ngā taha e rua. Ko te tau i tango i te kore ka hua ko tōna korenga.

$$-x^{2}=-81$$

Whakawehea ngā taha e rua ki te -1.

$$x^{2}=\frac{-81}{-1}$$

Ka taea te hautanga \frac{-81}{-1} te whakamāmā ki te 81 mā te tango tahi i te tohu tōraro i te taurunga me te tauraro.

$$x^{2}=81$$

Tuhia te pūtakerua o ngā taha e rua o te whārite.

$$x=9 x=-9$$

Ngā Upane e Whakamahi ana i te Tikanga Tātai Pūrua

Ko ngā tikanga tātai pūrua pēnei i tēnei nā, me te kīanga tau x^{2} engari kāore he kīanga tau x, ka taea tonu te whakaoti mā te whakamahi i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, ina tuhia ki te tānga ngahuru: ax^{2}+bx+c=0.

$$-x^{2}+81=0$$

Kei te āhua arowhānui tēnei whārite: ax^{2}+bx+c=0. Me whakakapi -1 mō a, 0 mō b, me 81 mō c i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\times 81}}{2\left(-1\right)}$$

Pūrua 0.

$$x=\frac{0±\sqrt{-4\left(-1\right)\times 81}}{2\left(-1\right)}$$

Whakareatia -4 ki te -1.

$$x=\frac{0±\sqrt{4\times 81}}{2\left(-1\right)}$$

Whakareatia 4 ki te 81.

$$x=\frac{0±\sqrt{324}}{2\left(-1\right)}$$

Tuhia te pūtakerua o te 324.

$$x=\frac{0±18}{2\left(-1\right)}$$

Whakareatia 2 ki te -1.

$$x=\frac{0±18}{-2}$$

Nā, me whakaoti te whārite x=\frac{0±18}{-2} ina he tāpiri te ±. Whakawehe 18 ki te -2.

$$x=-9$$

Nā, me whakaoti te whārite x=\frac{0±18}{-2} ina he tango te ±. Whakawehe -18 ki te -2.

$$x=9$$

Kua oti te whārite te whakatau.

$$x=-9 x=9$$