How do you find the number of sides in a polygon where four angles measure 100 degrees each and the remaining angles measure 160 degrees each?

To determine the number of sides in a polygon when given specific angle measures, we can use the formula for the sum of interior angles of a polygon. The formula is:

Sum of interior angles = (n – 2) × 180°

where n represents the number of sides in the polygon.

In this scenario, we have:

  • Four angles of 100 degrees each, contributing 4 × 100° = 400°
  • Let’s assume there are m angles measuring 160 degrees each. Thus, these angles contribute 160m°

The total sum of the angles can therefore be expressed as:

400° + 160m°

Setting this equal to the sum of interior angles formula, we have:

400 + 160m = (n - 2) × 180

Next, we know that the total number of angles in the polygon is the same as the number of sides, hence:

n = 4 + m

Now, substituting n in the angle sum equation:

400 + 160m = ((4 + m) - 2) × 180

Which simplifies to:

400 + 160m = (m + 2) × 180

Expanding the right-hand side gives:

400 + 160m = 180m + 360

Rearranging terms yields:

400 - 360 = 180m - 160m

Therefore:

40 = 20m

Solving for m results in:

m = 2

Now, substituting back to find n:

n = 4 + 2 = 6

Thus, the polygon has 6 sides, making it a hexagon.

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