Question

Fill in the blank so that 81x2+_

x+81 is a perfect square trinomial.
81x²+_____

x+81

Answer 1

the blank is 162

since 81 and 81 are both perfect squares the middle term (blank) will be the product of their roots times 2

√81=9

√81 =9

9 x 9 x 2

= 162