This is the kun'yomi reading for 引 and the on'yomi for 算. And the さん reading is rendaku'd into ざん. This is the same for all the math-ish words (addition, subtraction, multiplication, and division), so try to remember that, because you'll see it again!
Of course I can do subtraction!
Subtraction class is so long that I can't stop yawning.
What year of grade school will we learn subtraction?