Given that the triangle is acute.

So, ∠1, ∠2 and ∠3 be the angles of the triangle.

∠1 = 90^o (Given)

∠2 = ∠3

We know that,

∠1 + ∠2 + ∠3 = 180^o

90^o + ∠2 + ∠2 = 180^o

2∠2 = 180^o – 90^o

∠2 = 45^o

Therefore, ∠2 = ∠3 = 45^o

Thus, each acute angle is equal to 45^o.