Questions: Convert the polar coordinates S(16,135°) into rectangular coordinates. Do not use the polar-conversion function on your calculator.
A. (-8 sqrt(2),-8 sqrt(2))
B. (-8 sqrt(2), 8 sqrt(2))
C. (-8 sqrt(3), 8)
D. (8 sqrt(3), 8)
E. (8 sqrt(2), 8 sqrt(2))
Transcript text: 13. (L63) Convert the polar coordinates $S\left(16,135^{\circ}\right)$ into rectangular coordinates. Do not use the polar-conversion function on your calculator.
A. $(-8 \sqrt{2},-8 \sqrt{2})$
B. $(-8 \sqrt{2}, 8 \sqrt{2})$
C. $(-8 \sqrt{3}, 8)$
D. $(8 \sqrt{3}, 8)$
E. $(8 \sqrt{2}, 8 \sqrt{2})$
Solution
Solution Steps
Step 1: Recall the conversion formulas from polar to rectangular coordinates
To convert polar coordinates \( (r, \theta) \) to rectangular coordinates \( (x, y) \), use the formulas:
\[
x = r \cdot \cos(\theta)
\]
\[
y = r \cdot \sin(\theta)
\]
Step 2: Substitute the given polar coordinates into the formulas
Given \( S\left(16, 135^{\circ}\right) \), substitute \( r = 16 \) and \( \theta = 135^{\circ} \) into the formulas:
\[
x = 16 \cdot \cos(135^{\circ})
\]
\[
y = 16 \cdot \sin(135^{\circ})
\]
Step 3: Evaluate \( \cos(135^{\circ}) \) and \( \sin(135^{\circ}) \)
Using the unit circle:
\[
\cos(135^{\circ}) = -\frac{\sqrt{2}}{2}
\]
\[
\sin(135^{\circ}) = \frac{\sqrt{2}}{2}
\]
Step 4: Calculate \( x \) and \( y \)
Substitute the values of \( \cos(135^{\circ}) \) and \( \sin(135^{\circ}) \) into the formulas:
\[
x = 16 \cdot \left(-\frac{\sqrt{2}}{2}\right) = -8\sqrt{2}
\]
\[
y = 16 \cdot \left(\frac{\sqrt{2}}{2}\right) = 8\sqrt{2}
\]
Step 5: Write the rectangular coordinates
The rectangular coordinates are \( (-8\sqrt{2}, 8\sqrt{2}) \).