Question

a) (x - 2,5)^2 = 9

b)(1 - x)^3 = -8

c)2^4-x = 16

Answer 1

a) \(\left(x-2,5\right)^2=9\)

\(\Leftrightarrow\left[{}\begin{matrix}x-2,5=3\\x-2,5=-3\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=5,5\\x=-0,5\end{matrix}\right.\)

b) \(\left(1-x\right)^3=-8=\left(-2\right)^3\)

\(1-x=-2\)

\(x=3\)

c) \(2^4-x=16\)

\(16-x=16\)

\(x=0\)

Answer 2

\(a,\left(x-2,5\right)^2=9\)

\(+,TH1:x-2,5=3\)

\(\Rightarrow x=3+2,5\\\Rightarrow x=5,5\)

\(+,TH2:x-2,5=-3\)

\(\Rightarrow x=-3+2,5\\\Rightarrow x=-0,5\)

\(b,(1-x)^3=-8\)

\(\Rightarrow\left(1-x\right)^3=\left(-2\right)^3\)

\(\Rightarrow1-x=-2\)

\(\Rightarrow x=1-\left(-2\right)\)

\(\Rightarrow x=3\)

\(c,2^4-x=16\)

\(\Rightarrow16-x=16\)

\(\Rightarrow x=0\)

#\(Toru\)