Question

80-(5+80)=3-(x-7)

150-(2x+1)=150-29

* chỗ 2x nghĩa là 2 nhân x nha

tìm x

 

Answer 1

80-(5+80)=3-(x-7)

80-85=3-(x-7)

-5=3-(x-7)

3+(-5)=x-7

-2=x-7

7+(-2)=x

5=x

Answer 2

a/ \(80-\left(5+80\right)=3-\left(x-7\right)\)

\(\Leftrightarrow3-\left(x-7\right)=80-85=-5\)

\(\Leftrightarrow x-7=3-\left(-5\right)=8\)

\(\Rightarrow x=8+7=15\)

b/ \(150-\left(2x+1\right)=150-29=121\)

\(\Leftrightarrow2x+1=150-121=29\)

\(\Leftrightarrow2x=29-1=28\)
\(\Rightarrow x=28:2=14\)

Answer 3

150-(2x+1)=121

2x+1=150-121

2x+1=29

2x=29-1

2x=28

x=28:2

x=14