Answer:
10∠126.87°
r = 10; θ = 126.87°
Step-by-step explanation:
The coordinate conversion from (x, y) or (x +yi) to (r; θ) can be done using the relations ...
r = √(x² +y²)
θ = arctan(y/x) . . . . paying attention to quadrant
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For the given complex number, we have ...
r = √((-6)² +8²) = √(36 +64) = √100 = 10
θ = arctan(8/(-6)) = arctan(-4/3) . . . . in the 2nd quadrant
θ ≈ -53.13° +180° = 126.87°
The equivalence is ...
-6 +8i ⇔ 10∠126.87° . . . . . in the form r∠θ
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Additional comment
Many scientific and graphing calculators are equipped to work with complex numbers, including their conversion to or from polar form.
