<p>calibre. ;)</p>
<p>More math questions for me please :D</p>
<p>That problem wasn’t too hard as long as one noticed that ac + bd = 81 had to be multiplied by -2.</p>
<p>calibre. ;)</p>
<p>More math questions for me please :D</p>
<p>That problem wasn’t too hard as long as one noticed that ac + bd = 81 had to be multiplied by -2.</p>