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

1 Answer
Sep 19, 2016

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"#