Answer
$2x=3x-25$
$x=25$
Work Step by Step
"Twice" means multiply by 2. The term preceding "less" is a subtrahend. "Triple" means multiply by 3.
$2x=3x-25$ $\longrightarrow$addition property
$2x+25-2x=3x-25+25-2x$ $\longrightarrow$simplify
$25=x$