Fourth angle is 120,u can find it by ..........sum of all angles of a quadrilateral is 360...let the fourth angle be x360 = 75 + 90 + 75 + x ..........360 = 240 + x ..360 - 240 = x ..120 = x.............

Quadrilateral Angle Sum Property
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The sum of the interior angles of a quadrilateral is always equal to 360 degrees. Therefore, if we know the measures of three angles in a quadrilateral, we can find the measure of the fourth angle by subtracting the sum of the known angles from 360.

Given that three angles of the quadrilateral are 75, 90, and 75 degrees, we can find the fourth angle as follows:

Step 1: Find the sum of the known angles
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To find the sum of the known angles, we add their measures together:

75 + 90 + 75 = 240 degrees

Step 2: Find the measure of the fourth angle
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To find the measure of the fourth angle, we subtract the sum of the known angles from 360:

360 - 240 = 120 degrees

Hence, the measure of the fourth angle in the quadrilateral is 120 degrees.

Summary
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In summary, given that the three angles of a quadrilateral are 75, 90, and 75 degrees, we can find the measure of the fourth angle by subtracting the sum of the known angles from 360. The sum of the known angles is 240 degrees, and therefore, the measure of the fourth angle is 120 degrees.