Answer:
15°
Explanation:
We know sum of 3 angles is a triangle is always 180°.
Since, this is a right triangle, ONE ANGLE IS 90°. THus, the other two must sum 90.
Let one of the acute angles be x
Since the other is 5 times this, that one is 5x
Thus, now we can write:
x + 5x = 90
Solving for x:

Since x = 15, "5x" would be 5 * 15 = 75
THus, one acute angle is 15 and another is 75, so the smallest is 15