\(x\times92+x\times7+x=7900\)
\(\Rightarrow x\times\left(92+7+1\right)=7900\)
\(\Rightarrow x\times100=7900\)
\(\Rightarrow x=7900:100\)
\(\Rightarrow x=79\)
X x 92 + X x 7 + X = 7900
X x 92 + X x 7 + X x 1 = 7900
X x ( 92 + 7 + 1 ) = 7900
X x 100 = 7900
X = 7900 : 100
X = 79