a, - ( x + 84 ) + 213 = -16
=> - ( x + 84 ) = -16 - 213
=> - ( x + 84 ) =-229
=> x + 84 = 229
=> x = 145
b. x + ( -35 ) = 18
=> x = 18 - ( -35 )
=> x = 18 + 35
=> x = 53
c. -2x - ( - 17 ) = 15
=> -2x = 15 + ( -17)
=> -2x = -2
=> x = 1
\(a,-\left(x+84\right)+213=-16\)
\(x+84=213+16\)
\(x+84=229\)
\(x=229-84\)
\(x=145\)
\(b,x+\left(-35\right)=18\)
\(x=18+35\)
\(x=53\)
\(c,-2x-\left(-17\right)=15\)
\(-2x+17=15\)
\(2x=17-15\)
\(2x=2\)
\(x=1\)