các bạn giúp mik vs

\(\left(-216\right):9+7^5:7^3-\left(-4\right)^2.5\)

\(\Leftrightarrow\left(-24\right)+7^2-16\)

\(\Leftrightarrow\left(-24\right)+49-16\)

\(\Leftrightarrow25-16\)

\(\Leftrightarrow9\)

ra là một thanh niên lớp 6 trg hàn thuyên :D

\(3.\left(-5\right)^2+2.\left(-15\right)-20=3.25-2.15-20=75-30-20=25\)

bai 1

20:(24-(3^2.4-34)^2)-20

=20:(24-(9.4-34)^2)-20

=20:(24-2^2)-20

=20:20-20

=-19

bai 2

a

14+5x=4^6:4^3

14+5x=4^3

14+5x=64

5x=64-14

5x=50

x=50:5

x=10

b

189-2.(93-x)=59

2..(93-x)=189-59

2.(93-x)=130

(93-x)=130:2

93-x=65

x=93-65

x=28

1) \(20:\left[24-\left(3^2.4-34\right)^2\right]-20\)

\(=20:\left[24-\left(9.4-34\right)^2\right]-20\)

\(=20:\left[24-4\right]-20\)

\(=20:20-20\)

\(=1-20\)

\(=-19\)

2)a.\(14+5x=4^6:4^3\)

       \(14+5x=64\)

       \(5x=64-14\)

       \(5x=50\)

    \(\Rightarrow x=10\)

b)     189-2(93-x)=59

         2(93-x)       =189-59

        2(93-x)        =130

           93-x          =130:2

           93-x          =65

               x            =93-65

               x            =28

Học tốt nha!!!

\(\dfrac{5}{12}+\dfrac{-7}{12}=\dfrac{-2}{12}=\dfrac{-1}{6}\)

\(\dfrac{1}{2}+\dfrac{-2}{3}=\dfrac{3}{6}+\dfrac{-4}{6}=\dfrac{-1}{6}\)

\(\dfrac{3}{5}-\dfrac{4}{3}=\dfrac{9}{15}-\dfrac{20}{15}=\dfrac{-11}{15}\)

\(\dfrac{-15}{14}.\dfrac{21}{20}=\dfrac{-315}{280}=\dfrac{-9}{8}\)

\(\dfrac{-1}{6}\)

\(\dfrac{-1}{6}\)

\(\dfrac{-11}{15}\)

\(\dfrac{-9}{8}\)

a=240

b=45

c=-1700

=\(\left[\dfrac{\left(0,4.2\right)^5}{\left(0,4\right)^6}+\dfrac{2^9.2^6.3^8}{\left(3.2\right)^6.2^9}\right]=\left[\dfrac{\left(0,4\right)^5.2^5}{\left(0,4\right)^6}+\dfrac{2^6.3^8}{3^6.2^6}\right]\)

=\(\left[\dfrac{2^5}{0,4}+3^2\right]\)

=\(\left[80+9\right]=89\)

\(\left[\dfrac{\left(2.0,4\right)^5}{0,4,0,4^5}+\dfrac{2^{15}.3^8}{3^6.2^6.2^9}\right]\div\dfrac{3^{20}.5^{30}}{3^{15}.5^{30}}\)

\(=\left[\dfrac{2^5.0.4^5}{0,4.0,4^5}+\dfrac{2^{15}.3^8}{3^6.2^{15}}\right]\div3^5\)

\(=\left[\dfrac{2^5}{0,4}+3^2\right]\div243\)

\(=80+\left(3^5\div3^2\right)\)

\(=80+3^3\)

\(=80+27\)

\(=107\)

-17.25=-425

2.

5(-8).2(-3)=10.24=240

3(-5)²+2(-5)-20=15.5+(-2)5-4.5=(15-2-4).5=9.5=45

34.(15-10)-15(34-10)=34.15-34.10-15.34+15.10=0+(-34+15).10=-19.10=-190