ĐKXĐ: x>=0

\(\sqrt{x}=6,25\)

=>\(x=6,25^2=\dfrac{625}{16}\)

Ủa anh,ngta cho bt  căn x r thì đkxđ lm j ;-;;

\(x:\frac13+8,4\cdot\frac67\cdot\left\lbrack6-\frac{2,3+5:6,25}{8\cdot0,0125+6,9}\right\rbrack\)

\(=x\cdot3+1,2\cdot6\cdot\left\lbrack6-\frac{2,3+0,8}{0,1+6,9}\right\rbrack\)

\(=3x+7,2\cdot\left\lbrack6-3,1:7\right\rbrack=3x+7,2\cdot\frac{38.9}{7}=3x+\frac{280.08}{7}\)

\(5\frac47:\left\lbrace x:\frac13+8,4\cdot\frac67\cdot\left\lbrack6-\frac{2,3+5:6,25}{8\cdot0,0125+6,9}\right\rbrack\right\rbrace=1\frac{1}{14}\)

=>\(\frac{39}{7}:\left(3x+\frac{280.08}{7}\right)=\frac{15}{14}\)

=>\(3x+\frac{280.08}{7}=\frac{39}{7}:\frac{15}{14}=\frac{39}{7}\cdot\frac{14}{15}=2\cdot\frac{13}{5}=2\cdot2,6=5,2\)

=>\(3x=5,2-\frac{280.08}{7}=-\frac{243.68}{7}=\frac{-6092}{175}\)

=>\(x=-\frac{6092}{175\cdot3}=\frac{-6092}{525}\)

a)

\(\sqrt{x}=4\Rightarrow x=4^2=16\)

c) \(x\in\varnothing\)

e)  \(\sqrt{x}=6,25\Rightarrow x=\left(6,25\right)^2=39,0625\)

b) \(\sqrt{x}=\sqrt{7}\Rightarrow x=7\)

d) \(\sqrt{x}=0\Rightarrow x=0\)

Cách đánh đề độc lạ ghê:v

a: =>x=16

b: =>x=7

c: =>x thuộc rỗng

d: =>x=0

e: =>x=(25/4)^2=625/16

5.x = 6,25

         x = 6,25 : 5

         x = 1,25

và 5 + x = 6,25

      x = 6,25 – 5

      x = 1,25

\(\frac{x}{6,25}=\frac{x}{1,96}\)

\(\Rightarrow\frac{x}{6,25}-\frac{x}{1,96}=0\)

\(\Rightarrow x\left(\frac{1}{6,25}-\frac{1}{1,96}\right)=0\)

\(\Rightarrow x=0\). Do \(\frac{1}{6,25}-\frac{1}{1,96}\ne0\)

X x 2 + X x 0,5 = 6,25

X x (2 + 0,5) = 6,25

X x 2,5 = 6,25

X = 6,25 : 2,5 

X = 2,5

Nhớ k cho mình nhé

\(x\cdot2+x\cdot0,5=6,25\)

\(x\cdot\left(2+0,5\right)=6,25\)

\(x\cdot2,5=6,25\)

\(x=6,25:2,5=2,5\)

x và y đều bằng nhau dù là nhân hay cộng. 

6,25=2,5^2

\(x^2=6,25\Rightarrow x=-2,5\)