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-x^{2}+5x+24=0
Hurinahatia te pūrau ki te āhua tānga ngahuru. Whakaraupapahia ngā kīanga tau mai i te pū teitei rawa ki te mea iti rawa.
a+b=5 ab=-24=-24
Hei whakaoti i te whārite, whakatauwehea te taha mauī mā te whakarōpū. Tuatahi, me tuhi anō te taha mauī hei -x^{2}+ax+bx+24. Hei kimi a me b, whakaritea tētahi pūnaha kia whakaoti.
-1,24 -2,12 -3,8 -4,6
I te mea kua tōraro te ab, he tauaro ngā tohu o a me b. I te mea kua tōrunga te a+b, he nui ake te uara pū o te tau tōrunga i tō te tōraro. Whakarārangitia ngā tau tōpū takirua pērā katoa ka hoatu i te hua -24.
-1+24=23 -2+12=10 -3+8=5 -4+6=2
Tātaihia te tapeke mō ia takirua.
a=8 b=-3
Ko te otinga te takirua ka hoatu i te tapeke 5.
\left(-x^{2}+8x\right)+\left(-3x+24\right)
Tuhia anō te -x^{2}+5x+24 hei \left(-x^{2}+8x\right)+\left(-3x+24\right).
-x\left(x-8\right)-3\left(x-8\right)
Tauwehea te -x i te tuatahi me te -3 i te rōpū tuarua.
\left(x-8\right)\left(-x-3\right)
Whakatauwehea atu te kīanga pātahi x-8 mā te whakamahi i te āhuatanga tātai tohatoha.
x=8 x=-3
Hei kimi otinga whārite, me whakaoti te x-8=0 me te -x-3=0.
-x^{2}+5x+24=0
Ko ngā whārite katoa o te āhua ax^{2}+bx+c=0 ka taea te whakaoti mā te whakamahi i te tikanga tātai pūrua: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. E rua ngā otinga ka puta i te tikanga tātai pūrua, ko tētahi ina he tāpiri a ±, ā, ko tētahi ina he tango.
x=\frac{-5±\sqrt{5^{2}-4\left(-1\right)\times 24}}{2\left(-1\right)}
Kei te āhua arowhānui tēnei whārite: ax^{2}+bx+c=0. Me whakakapi -1 mō a, 5 mō b, me 24 mō c i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-5±\sqrt{25-4\left(-1\right)\times 24}}{2\left(-1\right)}
Pūrua 5.
x=\frac{-5±\sqrt{25+4\times 24}}{2\left(-1\right)}
Whakareatia -4 ki te -1.
x=\frac{-5±\sqrt{25+96}}{2\left(-1\right)}
Whakareatia 4 ki te 24.
x=\frac{-5±\sqrt{121}}{2\left(-1\right)}
Tāpiri 25 ki te 96.
x=\frac{-5±11}{2\left(-1\right)}
Tuhia te pūtakerua o te 121.
x=\frac{-5±11}{-2}
Whakareatia 2 ki te -1.
x=\frac{6}{-2}
Nā, me whakaoti te whārite x=\frac{-5±11}{-2} ina he tāpiri te ±. Tāpiri -5 ki te 11.
x=-3
Whakawehe 6 ki te -2.
x=-\frac{16}{-2}
Nā, me whakaoti te whārite x=\frac{-5±11}{-2} ina he tango te ±. Tango 11 mai i -5.
x=8
Whakawehe -16 ki te -2.
x=-3 x=8
Kua oti te whārite te whakatau.
-x^{2}+5x+24=0
Ko ngā whārite pūrua pēnei i tēnei nā ka taea te whakaoti mā te whakaoti i te pūrua. Hei whakaoti i te pūrua, ko te whārite me mātua tuhi ki te āhua x^{2}+bx=c.
-x^{2}+5x+24-24=-24
Me tango 24 mai i ngā taha e rua o te whārite.
-x^{2}+5x=-24
Mā te tango i te 24 i a ia ake anō ka toe ko te 0.
\frac{-x^{2}+5x}{-1}=-\frac{24}{-1}
Whakawehea ngā taha e rua ki te -1.
x^{2}+\frac{5}{-1}x=-\frac{24}{-1}
Mā te whakawehe ki te -1 ka wetekia te whakareanga ki te -1.
x^{2}-5x=-\frac{24}{-1}
Whakawehe 5 ki te -1.
x^{2}-5x=24
Whakawehe -24 ki te -1.
x^{2}-5x+\left(-\frac{5}{2}\right)^{2}=24+\left(-\frac{5}{2}\right)^{2}
Whakawehea te -5, te tau whakarea o te kīanga tau x, ki te 2 kia riro ai te -\frac{5}{2}. Nā, tāpiria te pūrua o te -\frac{5}{2} ki ngā taha e rua o te whārite. Mā konei e pūrua tika tonu ai te taha mauī o te whārite.
x^{2}-5x+\frac{25}{4}=24+\frac{25}{4}
Pūruatia -\frac{5}{2} mā te pūrua i te taurunga me te tauraro o te hautanga.
x^{2}-5x+\frac{25}{4}=\frac{121}{4}
Tāpiri 24 ki te \frac{25}{4}.
\left(x-\frac{5}{2}\right)^{2}=\frac{121}{4}
Tauwehea x^{2}-5x+\frac{25}{4}. Ko te tikanga pūnoa, ina ko x^{2}+bx+c he pūrua tika pūrua tika pū, ka taea taua mea te tauwehea i ngā wā katoa hei \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-\frac{5}{2}\right)^{2}}=\sqrt{\frac{121}{4}}
Tuhia te pūtakerua o ngā taha e rua o te whārite.
x-\frac{5}{2}=\frac{11}{2} x-\frac{5}{2}=-\frac{11}{2}
Whakarūnātia.
x=8 x=-3
Me tāpiri \frac{5}{2} ki ngā taha e rua o te whārite.