Answer:-
The measure if ∠x
![\large\leadsto\boxed{\tt\purple{43^(\circ)}}](https://img.qammunity.org/2022/formulas/mathematics/college/3kw8smzw5x50caulgk65pv66qrvh9vajkg.png)
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• To Find:-
- Measure of
x
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• Solution:-
The given angles are made by a straight line. We know that the total angle made by a straight line is 180°.
Therefore, all the angles should sum upto 180°.
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• Working:-
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![\sf (x + 31^(\circ)) + (x + 20^(\circ)) + (x) = 180^(\circ)](https://img.qammunity.org/2022/formulas/mathematics/college/c01cvntumhwkf4mvh37k2c5y1gvunlms81.png)
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➪
![\sf x + 31^(\circ) + x + 20^(\circ) + x = 180^(\circ)](https://img.qammunity.org/2022/formulas/mathematics/college/k9207pllz1kubzn2c01xccf53qfi6x0y5m.png)
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➪
![\sf 3x + 51^(\circ) = 180^(\circ)](https://img.qammunity.org/2022/formulas/mathematics/college/4smadf18i1j0t79cfx5c5sbiy057dcdyur.png)
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➪
![\sf 3x = 180^(\circ) - 51^(\circ)](https://img.qammunity.org/2022/formulas/mathematics/college/fr26fkobbf52yh5m4n7pajf1lofihoqlzy.png)
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➪
![\sf 3x = 129^(\circ)](https://img.qammunity.org/2022/formulas/mathematics/college/5loxns7hqa4bs4wq6pmpf90pewx73kuet7.png)
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![\sf x = (129)/(3)](https://img.qammunity.org/2022/formulas/mathematics/college/zldtgjsmkgt8gr89s8oofs62ksuomcoslb.png)
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★
![\large{\bold\red{x = 43^(\circ)}}](https://img.qammunity.org/2022/formulas/mathematics/college/y52ziuqhdpqjx05v0h2mngqswu8rt2jbvp.png)
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Therefore, the measure of the ∠x is 43°.