Answer:
3. A=B=70°; C=D=110°
4. A=90°; C=48°
Explanation:
Same-side angles of a trapezoid add to 180°.
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3. (2x) +(x+15) = 180
3x + 15 = 180 . . . . simplify
x +5 = 60 . . . . . . . divide by 3
x = 55
A=B=(x+15)° = (55+15)° = 70°
C=D=2x° = 2·55° = 110°
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4. You are given the values of one of the angles on each side, so the other can be found by subtraction:
A=180°-D = 90°
C = 180° -132° = 48°