15. a) [tex] \frac{ \sqrt{196}- 2^{2}* \sqrt{ \frac{121}{144} } }{x}= \frac{ \sqrt{1296}+ \sqrt{729}- 2^{5} }{ 3^{4}- 3^{3}- 3^{2}-3 } [/tex]
[tex]\frac{ \sqrt{196}- 2^{2}* \sqrt{ \frac{121}{144} } }{x}= \frac{ \sqrt{1296}+ \sqrt{729}- 2^{5} }{ 3^{4}- 3^{3}- 3^{2}-3 }, x \neq 0[/tex]
[tex] \frac{14-4* \frac{11}{12} }{x}= \frac{36+27-32}{81-27-9-3} [/tex]
[tex] \frac{14- \frac{11}{3} }{x} = \frac{31}{42} [/tex]
[tex] \frac{ \frac{31}{3} }{x} = \frac{31}{42} [/tex]
[tex] \frac{31}{3x}= \frac{31}{42} [/tex]
3x=42
3x:3=42:3
x=14, x≠0
b) [tex] \frac{0.5* \sqrt{ \frac{81}{625} }+0.8 }{0.6* \sqrt{576}+ 2^{2} } = \frac{0.4* \sqrt{0.25} }{x} [/tex]
[tex]\frac{0.5* \sqrt{ \frac{81}{625} }+0.8 }{0.6* \sqrt{576}+ 2^{2} } = \frac{0.4* \sqrt{0.25} }{x} , x \neq 0[/tex]
[tex] \frac{ \frac{1}{2}* \frac{9}{25}* \frac{4}{5} }{0.6*24+4}= \frac{ \frac{2}{5}* \sqrt{ \frac{1}{4} } }{x} [/tex]
[tex] \frac{ \frac{9}{50}+ \frac{4}{5} }{14.4+4} = \frac{ \frac{2}{5}* \frac{1}{2} }{x} [/tex]
[tex] \frac{ \frac{49}{50} }{18.4}= \frac{ \frac{1}{5} }{x} [/tex]
[tex] \frac{ \frac{49}{50} }{ \frac{92}{5} }= \frac{1}{5x} [/tex]
[tex] \frac{49}{920}= \frac{1}{5x} [/tex]
49*5x=1*920
245x=920
245x:245=920:245
[tex]x= \frac{920}{245} [/tex]
[tex]x= \frac{184}{49} [/tex],x≠0 ≈ [tex]x=3 \frac{37}{49} [/tex] x≈3.7551
c) [tex] \frac{x}{(1* \frac{2}{3}) ^{2}* \sqrt{0.0009}+4 ^{-1} }= \frac{ \sqrt{1089} }{ \sqrt{0.36+(2* \frac{1}{2}) ^{-1} } } [/tex]
[tex] \frac{x}{( \frac{2}{3} )^{2} * \sqrt{ \frac{9}{10000} }+ \frac{1}{4} }= \frac{33}{ \sqrt{ \frac{9}{25} }+1 ^{-1} } [/tex]
[tex] \frac{x}{ \frac{4}{9} * \frac{3}{100}+ \frac{1}{4} }= \frac{33}{ \frac{3}{5} +1} [/tex]
[tex] \frac{x}{ \frac{1}{3}* \frac{1}{25}+ \frac{1}{4} }= \frac{33}{ \frac{8}{5} } [/tex]
[tex] \frac{x}{ \frac{1}{75}+ \frac{1}{4} }= \frac{165}{8} [/tex]
[tex] \frac{x}{ \frac{79}{300} }= \frac{165}{8} [/tex]
[tex] \frac{300x}{79}= \frac{165}{8} [/tex]
8*300x=165*79
2400x=13035
2400x:2400=13035:2400
[tex]x= \frac{13035}{2400} [/tex]
[tex]x= \frac{869}{160} [/tex] ≈ [tex]x=5 \frac{69}{160} [/tex], ≈ x=5.43125
