Question

[PASSIN]

Tìm x, biết:

a, \(x-\left(\frac{50x}{100}+\frac{25x}{200}\right)=11\frac{1}{4}\)                                         b,\(\left(x-5\right).\frac{30}{100}=\frac{200x}{100}+5\)

c,\(\frac{x+1}{2}=\frac{8}{x+1}\)                                                                d, \(x:\left(9\frac{1}{2}-\frac{3}{2}\right)=\frac{0,4+\frac{2}{9}-\frac{2}{11}}{1,6+\frac{8}{9}-\frac{8}{11}}\)

Answer 1

[phạm văn tuấn]

\(c,\frac{x+1}{2}=\frac{8}{x+1}\)

\(\Rightarrow(x+1)(x+1)=2.8\)

\(\Rightarrow(x+1)^2=16\)

\(\Rightarrow(x+1)^2=4^2\)

\(\Rightarrow x+1=4\)

\(\Rightarrow x=4-1\)

\(\Rightarrow x=3\)

Answer 2

[phạm văn tuấn]

\(a,x-(\frac{50x}{100}+\frac{25x}{200})=11\frac{1}{4}\)

\(\Rightarrow x-\frac{50x+25x}{100}=\frac{45}{4}\)

\(\Rightarrow\frac{100x}{100}-\frac{75x}{100}=\frac{45}{4}\)

\(\Rightarrow\frac{100x-75x}{100}=\frac{1125}{100}\)

\(\Rightarrow25x=1125\)

\(\Rightarrow x=45\)