Respuesta :

∠A and ∠B are supplementary, then:

m∠A + m∠B = 180°

112° + m∠B = 180°

m∠B = 180° - 112°

m∠B = 68°

The addition of the three internal angles of a triangle is equal to 180°, then:

m∠B + m∠J + 90° = 180°

68° + m∠J + 90° = 180°

m∠J = 180° - 90° - 68°

m∠J = 22°

RELAXING NOICE
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