Step-by-step explanation:
Blue is for physics........
∠1 + ∠3 + 90° = 180°
∠1 + ∠3 = 90°
∠3 = ∠4 (vertically opposite angles)
∠1 + ∠4 = 90°
Therefore, the answer is ∠1 + ∠4
So 10 % of 40 is 4
5% of 40 is 2
so 15% is 6
then you have to do 40-6
and then you get the answer of 34
