Tīpoka ki ngā ihirangi matua
Whakaoti mō y
Tick mark Image
Graph

Ngā Raru Ōrite mai i te Rapu Tukutuku

Tohaina

0=17y-2y^{2}-8
Whakamahia te āhuatanga tuaritanga hei whakarea te 2y-1 ki te 8-y ka whakakotahi i ngā kupu rite.
17y-2y^{2}-8=0
Whakawhitihia ngā taha kia puta ki te taha mauī ngā kīanga tau taurangi katoa.
-2y^{2}+17y-8=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=17 ab=-2\left(-8\right)=16
Hei whakaoti i te whārite, whakatauwehea te taha mauī mā te whakarōpū. Tuatahi, me tuhi anō te taha mauī hei -2y^{2}+ay+by-8. Hei kimi a me b, whakaritea tētahi pūnaha kia whakaoti.
1,16 2,8 4,4
I te mea kua tōrunga te ab, he ōrite te tohu o a me b. I te mea kua tōrunga te a+b, he tōrunga hoki a a me b. Whakarārangitia ngā tau tōpū takirua pērā katoa ka hoatu i te hua 16.
1+16=17 2+8=10 4+4=8
Tātaihia te tapeke mō ia takirua.
a=16 b=1
Ko te otinga te takirua ka hoatu i te tapeke 17.
\left(-2y^{2}+16y\right)+\left(y-8\right)
Tuhia anō te -2y^{2}+17y-8 hei \left(-2y^{2}+16y\right)+\left(y-8\right).
2y\left(-y+8\right)-\left(-y+8\right)
Tauwehea te 2y i te tuatahi me te -1 i te rōpū tuarua.
\left(-y+8\right)\left(2y-1\right)
Whakatauwehea atu te kīanga pātahi -y+8 mā te whakamahi i te āhuatanga tātai tohatoha.
y=8 y=\frac{1}{2}
Hei kimi otinga whārite, me whakaoti te -y+8=0 me te 2y-1=0.
0=17y-2y^{2}-8
Whakamahia te āhuatanga tuaritanga hei whakarea te 2y-1 ki te 8-y ka whakakotahi i ngā kupu rite.
17y-2y^{2}-8=0
Whakawhitihia ngā taha kia puta ki te taha mauī ngā kīanga tau taurangi katoa.
-2y^{2}+17y-8=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.
y=\frac{-17±\sqrt{17^{2}-4\left(-2\right)\left(-8\right)}}{2\left(-2\right)}
Kei te āhua arowhānui tēnei whārite: ax^{2}+bx+c=0. Me whakakapi -2 mō a, 17 mō b, me -8 mō c i te tikanga tātai pūrua, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-17±\sqrt{289-4\left(-2\right)\left(-8\right)}}{2\left(-2\right)}
Pūrua 17.
y=\frac{-17±\sqrt{289+8\left(-8\right)}}{2\left(-2\right)}
Whakareatia -4 ki te -2.
y=\frac{-17±\sqrt{289-64}}{2\left(-2\right)}
Whakareatia 8 ki te -8.
y=\frac{-17±\sqrt{225}}{2\left(-2\right)}
Tāpiri 289 ki te -64.
y=\frac{-17±15}{2\left(-2\right)}
Tuhia te pūtakerua o te 225.
y=\frac{-17±15}{-4}
Whakareatia 2 ki te -2.
y=-\frac{2}{-4}
Nā, me whakaoti te whārite y=\frac{-17±15}{-4} ina he tāpiri te ±. Tāpiri -17 ki te 15.
y=\frac{1}{2}
Whakahekea te hautanga \frac{-2}{-4} ki ōna wāhi pāpaku rawa mā te tango me te whakakore i te 2.
y=-\frac{32}{-4}
Nā, me whakaoti te whārite y=\frac{-17±15}{-4} ina he tango te ±. Tango 15 mai i -17.
y=8
Whakawehe -32 ki te -4.
y=\frac{1}{2} y=8
Kua oti te whārite te whakatau.
0=17y-2y^{2}-8
Whakamahia te āhuatanga tuaritanga hei whakarea te 2y-1 ki te 8-y ka whakakotahi i ngā kupu rite.
17y-2y^{2}-8=0
Whakawhitihia ngā taha kia puta ki te taha mauī ngā kīanga tau taurangi katoa.
17y-2y^{2}=8
Me tāpiri te 8 ki ngā taha e rua. Ko te tau i tāpiria he kore ka hua koia tonu.
-2y^{2}+17y=8
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.
\frac{-2y^{2}+17y}{-2}=\frac{8}{-2}
Whakawehea ngā taha e rua ki te -2.
y^{2}+\frac{17}{-2}y=\frac{8}{-2}
Mā te whakawehe ki te -2 ka wetekia te whakareanga ki te -2.
y^{2}-\frac{17}{2}y=\frac{8}{-2}
Whakawehe 17 ki te -2.
y^{2}-\frac{17}{2}y=-4
Whakawehe 8 ki te -2.
y^{2}-\frac{17}{2}y+\left(-\frac{17}{4}\right)^{2}=-4+\left(-\frac{17}{4}\right)^{2}
Whakawehea te -\frac{17}{2}, te tau whakarea o te kīanga tau x, ki te 2 kia riro ai te -\frac{17}{4}. Nā, tāpiria te pūrua o te -\frac{17}{4} ki ngā taha e rua o te whārite. Mā konei e pūrua tika tonu ai te taha mauī o te whārite.
y^{2}-\frac{17}{2}y+\frac{289}{16}=-4+\frac{289}{16}
Pūruatia -\frac{17}{4} mā te pūrua i te taurunga me te tauraro o te hautanga.
y^{2}-\frac{17}{2}y+\frac{289}{16}=\frac{225}{16}
Tāpiri -4 ki te \frac{289}{16}.
\left(y-\frac{17}{4}\right)^{2}=\frac{225}{16}
Tauwehea y^{2}-\frac{17}{2}y+\frac{289}{16}. 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(y-\frac{17}{4}\right)^{2}}=\sqrt{\frac{225}{16}}
Tuhia te pūtakerua o ngā taha e rua o te whārite.
y-\frac{17}{4}=\frac{15}{4} y-\frac{17}{4}=-\frac{15}{4}
Whakarūnātia.
y=8 y=\frac{1}{2}
Me tāpiri \frac{17}{4} ki ngā taha e rua o te whārite.