determine o conjunto solução de cada uma das seguintes equações
ME AJUDEMMMM E PRA AMANHÃ
Respostas
Resposta:
a)
\begin{gathered} {x}^{2} - 15x = 0 \\ x(1x - 15x) = 0 \\ x = 0 \\ x = 14\end{gathered}
x
2
−15x=0
x(1x−15x)=0
x=0
x=14
b)
\begin{gathered} {x}^{2} - 81 = 0 \\ x = \sqrt{81 \\ } \\ x = 9 \\ x = 0\end{gathered}
c)
\begin{gathered} {x}^{2} - 121 = 0 \\ x = \sqrt{121} \\ x = 11 \\ x = 0\end{gathered}
x
2
−121=0
x=
121
x=11
x=0
d)
\begin{gathered}3 {x}^{2} - x = 0 \\ x(3x - 1x) = 0 \\ x = 0 \\ 2x = 0 \\ x = 2\end{gathered}
3x
2
−x=0
x(3x−1x)=0
x=0
2x=0
x=2
e)
\begin{gathered} {x}^{2} - x = 0 \\ x(x - x) = 0 \\ x = 0 \\ x = 0\end{gathered}
x
2
−x=0
x(x−x)=0
x=0
x=0
f)
\begin{gathered}9 {x}^{2} - 16 = 0 \\ 9 {x}^{2} = 16 \\ x = \sqrt{16} \sqrt{9} \\ x = - 4. - 3 \\ x = 3.4\end{gathered}
9x
2
−16=0
9x
2
=16
x=
16
9
x=−4.−3
x=3.4
g)
\begin{gathered} {x}^{2} + 25 = 0 \\ x = \sqrt{25} \\ x = 5 \\ x = 0\end{gathered}
x
2
+25=0
x=
25
x=5
x=0
h)
\begin{gathered}11 {x}^{2} - x = 0 \\ x(11- x) = 0 \\ x = 0 \\ x = 11 \end{gathered}
11x
2
−x=0
x(11−x)=0
x=0
x=11
i)
\begin{gathered}49 {x}^{2} = 36 \\ x = \sqrt{36} \sqrt{49} \\x = 6 \: e \: 7\\ x = - 6 \: e \: - 7\end{gathered}
49x
2
=36
x=
36
49
x=6e7
x=−6e−7
j)
\begin{gathered}3 {x}^{2} - 27x = 0 \\ x(3 - 27x) = 0 \\ x = \frac{3}{27} \\ x = 9 \\ x = 0\end{gathered}
3x
2
−27x=0
x(3−27x)=0
x=
27
3
x=9
x=0
k)
\begin{gathered} {x}^{2} - 14 = 0 \\x(x - 14) = 0 \\ x = 14 \\ x = 0\end{gathered}
x
2
−14=0
x(x−14)=0
x=14
x=0
l)
\begin{gathered} - 25 {x}^{2} - 15 = 0 \\ x - 15 = \sqrt{25} \\ x - 15 = 5 \\ x = 5 + 15 \\ x = 20 \\ x = 0\end{gathered}
−25x
2
−15=0
x−15=
25
x−15=5
x=5+15
x=20
x=0