S* quadrilateral has angles IDD', 80', and 70°. Find the missing angle.olve these questions
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We have a quadrilateral with three known angles: one hundred degrees, eighty degrees, and seventy degrees. We need to find the fourth missing angle. The key fact we'll use is that the sum of all interior angles in any quadrilateral is always three hundred sixty degrees.
Now let's solve this step by step. First, we add all the known angles together. One hundred degrees plus eighty degrees plus seventy degrees equals two hundred fifty degrees. This gives us the sum of the three known angles.
Now for step two. Since the sum of all angles in a quadrilateral must equal three hundred sixty degrees, we subtract the sum of known angles from three hundred sixty degrees. Three hundred sixty minus two hundred fifty equals one hundred ten degrees. Therefore, the missing angle is one hundred ten degrees.
Let's verify our answer by checking that all four angles add up to three hundred sixty degrees. One hundred plus eighty plus seventy plus one hundred ten equals three hundred sixty degrees. Perfect! This confirms that our answer of one hundred ten degrees is correct.
To summarize: we used the fact that all interior angles in a quadrilateral sum to three hundred sixty degrees. We added the three known angles to get two hundred fifty degrees, then subtracted this from three hundred sixty degrees to find the missing angle of one hundred ten degrees.