Question

How do you plot `-8+3i` and find its absolute value?

Answer 1

see explanation.

Explanation:

From the origin, move 8 units to the left along the `color(blue)"real axis"` then at right angles at this point move vertically upwards, parallel to the `color(blue)"imaginary axis "`for 3 units.

This is the point (-8 ,3)

Since there is a right triangle formed from

`0to-8to3to0` we can use Pythagoras' theorem to calculate it's magnitude, which is the distance from the origin to the point (-8 ,3)

`rArrsqrt(8^2+3^2)=sqrt73larr" absolute value"`