Prove that a triangle is 180°.find value of 'x" and all angles, if they are (2x+7)° ,(2x-25)°,and (3x-12)°.please
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Answered by
8
(2x-7),(x+25)and (3x+12) are the angle.
Their sum is 180°.
⇒2x-7+x+25+3x+12 =180°
⇒6x+30 = 180°
⇒6x=150 ⇒x= 25
So the angles are 43°,50°,87°.
Their sum is 180°.
⇒2x-7+x+25+3x+12 =180°
⇒6x+30 = 180°
⇒6x=150 ⇒x= 25
So the angles are 43°,50°,87°.
Answered by
7
(2× +7) + (2× -25) + (3× - 12 ) = 180
2x + 7 + 2× - 25 + 3× -12 = 180
7× - 30 = 180
7× = 180 + 30
7× = 210
× = 210 / 7
× = 30
1st angle = 2 × + 7 = 67 degree
2nd angle = 2× - 25 = 35 degree
3rd angle = 3× -12 = 78 degree
67 + 35 + 78 = 180 degree proved.
2x + 7 + 2× - 25 + 3× -12 = 180
7× - 30 = 180
7× = 180 + 30
7× = 210
× = 210 / 7
× = 30
1st angle = 2 × + 7 = 67 degree
2nd angle = 2× - 25 = 35 degree
3rd angle = 3× -12 = 78 degree
67 + 35 + 78 = 180 degree proved.
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