Answer :
[tex]\sqrt{14\cdot15}=\sqrt{2\cdot7\cdot3\cdot5}=\\\vdots\
Any\ number\ does\ not\ repe at\ \vdots\\\\=\sqrt{210}\\\\\\\sqrt{210}\approx14.4914[/tex]
well I know 14 times 15 = 210 but I cant tell what is a square root since I am just in 4th grade.