A quadrilateral has interior angles of 85 degrees, 95 degrees, 100 degrees and one unknown angle. Select all the statements that are true of this quadrilateral.

Erklärung

Adding 85, 95 and 100 gives 280 degrees, and since the four interior angles must reach 360 degrees the unknown one is 360 minus 280. Starting from 180 degrees applies a three-sided total to a four-sided shape, which would leave a negative amount for the missing angle.