Question

tìm x biết:

a,60+(26-3 nhân x):5=64

b,1236-(4 nhân x-124)=4^4 nhân 4^15:4^16+2^3

c,3^x:3^5=81 nhân 3^6

d,2 nhân x-1234+264=786

Answer 1

a. \(69+\left(26-3x\right):5=64\)

\(\left(26-3x\right):5=64+60=124\)

\(\left(26-3x\right)=64:5=\dfrac{64}{5}\)

\(3x=26-\dfrac{64}{5}=\dfrac{66}{5}\)

\(x=\dfrac{66}{5}:3=\dfrac{22}{5}\)

Vậy...

b. \(1236-\left(4x-124\right)=4^4.4^{15}:4^{16}+2^3\)

\(1236-\left(4x-124\right)=64+8=72\)

\(\left(4x-124\right)=1236-72=1164\)

\(4x=1164+124=1288\)

\(x=1288:4=322\)

Vậy...

c. \(3^x:3^5=81.3^6\)

\(3^x:3^5=59049=3^{10}\)

\(\Rightarrow x:5=10\)

\(\Rightarrow x=10:5=2\)

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d, \(2.x-1234+264=786\)

\(2x=786+1234-264\)

\(2x=1756\Rightarrow x=878\)

Vậy...