Respuesta :

tonb

Answer:

143°

Step-by-step explanation:

The sum of angles in a triangle should be 180, so ∠1 = 180-53-90 = 37.

∠1 and ∠3 should add up to 180, so ∠3 must be 180-37 = 143.

Answer:

143

Step-by-step explanation:

if m(1) = 53

in triangle EDF , all angles sum is 180

90 +  53 + m(2) = 180

m(2) = 180-143

= 37

m(2) + m(3) = 180 as it is straight line

m(3) = 180 - 37

= 143