Respuesta :

We have 9^2 = 81 and 10^2 = 100;

So, 81 < 87 < 100;

9^2 < 87 < ( 9 + 1 )^2;

9 < [tex] \sqrt{87} [/tex] < 10;

Finally, [tex] \sqrt{87} [/tex] is irrational.