a. \(\left(x+5\right)+\left(x+9\right)=x+2\)
\(\Leftrightarrow\) \(x+5+x+9=x+2\)
\(\Leftrightarrow2x+14=x+2\)
\(\Leftrightarrow x=-12\)
b. \(\left(27-x\right)+\left(15+x\right)=x-24\)
\(\Leftrightarrow27-x+15+x=x-24\)
\(\Leftrightarrow x-24=42\)
\(\Leftrightarrow x=66\)
\(a,\left(x+5\right)+\left(x+9\right)=x+2\)
\(x+5+x+9=x+2\)
\(2x+14=x+2\)
\(2x+14-x-2=0\)
\(x+12=0\)
\(x=-12\)
\(b,\left(27-x\right)+\left(15+x\right)=x-24\)
\(27-x+15+x=x-24\)
\(42=x-24\)
\(x=66\)
a) (x+5)+(x+9)=x+2
⇒2x+14=x+2
⇒2x-x=2-14
⇒x=-12
Vậy x=-12
b) (27-x)+(15+x)=x-24
⇒42=x-24
⇒-x=-24-42
⇒x=66
vậy x=66
(x + 5) + (x + 9) = x + 2
\(\Rightarrow\) x + 5 + x + 9 = x + 2
\(\Rightarrow\) 2x + 14 = x + 2
\(\Rightarrow\) 2x + 14 - x - 2 = 0
\(\Rightarrow\) x + 12 = 0
\(\Rightarrow\) x = -12
Vậy x = -12
b, (27 - x) + (15 + x) = x - 24
\(\Rightarrow\) 27 - x + 15 + x - x + 24 = 0
\(\Rightarrow\) 66 - x = 0
\(\Rightarrow\) x = 66
Vậy x = 66
Chúc bạn học tốt!