A decagon has 10 sides. One angle of a regular decagon measures (8w + 17)°. Determine the value of w. Round to the nearest whole number.

w = 144
w = 23
w = 16
w = 8

1 answer

To find the value of \( w \) for the angle \( (8w + 17)^\circ \) in a regular decagon, we first need to calculate the measure of each interior angle of a regular decagon.

The formula for the measure of each interior angle of a regular polygon is given by:

\[ \text{Interior Angle} = \frac{(n-2) \times 180}{n} \]

where \( n \) is the number of sides. For a decagon, \( n = 10 \):

\[ \text{Interior Angle} = \frac{(10-2) \times 180}{10} = \frac{8 \times 180}{10} = \frac{1440}{10} = 144^\circ \]

Now we set the equation for the angle \( (8w + 17)^\circ \) equal to \( 144^\circ \):

\[ 8w + 17 = 144 \]

Next, we will solve for \( w \):

  1. Subtract \( 17 \) from both sides:

\[ 8w = 144 - 17 \]

\[ 8w = 127 \]

  1. Now, divide both sides by \( 8 \):

\[ w = \frac{127}{8} \]

Calculating \( \frac{127}{8} \):

\[ w = 15.875 \]

Rounding this to the nearest whole number gives:

\[ w \approx 16 \]

Thus, the value of \( w \) is \( \boxed{16} \).