Can anyone help me solve these ?

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.

x= cost per bracelet

number of bracelets * x + shipping charge = total cost

so

9x+9=72