Page 3 - ln1

We know that, Sum of interior opposite angles of a triangle = Exterior angle

x =50 +60 = 110
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By angle sum property,

Sum of interior angles = 180
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50 +60 +y=180 ∘
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=>110 +y=180 ∘
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=> y=180 −110 =70 ∘
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3. The three angles of a triangle are in the ratio 1: 2: 3 then find the measure of three angles.

We know that, the total measure of the three angles of a triangle is 180 .
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X + 2X + 3X = 180 ∘
6X = 180 ∘
=>X = 180 /6 = 30 ∘
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2X = 60 , 3X = 90
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Hence, the measures of the angles are 30 , 60 , 90 .
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