What is the length of MN?

MN = 6

This is because the shapes are dialations of each other

So PO and ML are the same side of the triangles but ML is dialated by a factor of 3.5 so that applies to the whole shape. So 21/3.5 = 6

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.

step-by-step explanation: