"What about giving imaginary numbers their own number line!" cried Betty.

"That's a fantastic idea!" cheered John with great gusto. "And I've got another great idea. Why don't we make our imaginary number line perpendicular to the real number line through the origin."

"What is the point of that?" asked Betty.

"Well," said John, "then not only will we have a place for imaginary numbers like 5i and -3i but also for complex numbers like 2+4i and
-2 - 5i."

Betty was speechless. "That's brilliant!" she said. "Its like we now have a visual way for looking at complex numbers."