Question

bài 1

1) 45 - 3 (x-2) = 12

2) 120 : [ 3(x - 25 ) ] = 10

Answer 1

\(1,45-3\left(x-2\right)=12\\ =>3\left(x-2\right)=45-12\\ =>3\left(x-2\right)=33\\ =>x-2=33:3\\ =>x-2=11\\ =>x=11+2=13\\ 2,120:\left[3\left(x-25\right)\right]=10\\ =>3\left(x-25\right)=120:10\\ =>3\left(x-25\right)=12\\ =>x-25=12:3\\ =>x-25=4\\ =>x=4+25=29\)

Answer 2

\(45-3\left(x-2\right)=12\)

\(-3\left(x-2\right)=12-45\)

\(-3\left(x-2\right)=-33\)

\(x-2=-33:\left(-3\right)\)

\(x-2=11\)

\(x=11+2\)

\(x=13\)

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\(120:\left[3\left(x-25\right)\right]=10\)

\(3\left(x-25\right)=120:10\)

\(3\left(x-25\right)=12\)

\(x-25=12:3\)

\(x-25=4\)

\(x=4+25\)

\(x=29\)

Answer 3

1) X = 13

2) X = 29