Question

in a ∆DEF , if angle E = 105° and angle F = 40° , find angle D​

Answer 1

Answer:

Step-by-step explanation:

sum of all angles in a triangle = 180°

so 105° + 40° + ∠d = 180°

=>145° + ∠d = 180°

=> ∠d = 180° - 145°

=> ∠d = 35°

hope this helps you

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Answer 2

According to Angle Sum Property of a triangle, Sum of all the angles in a triangle results in 180°.

So, in ∆DEF

∠D + ∠E + ∠F = 180°

∠D + 105° + 40° = 180°

∠D + 145° = 180°

∴∠D = 180°- 145°

= 35°

Hope it helps you.

Start a great tomorrow. :)