In a right-angled triangle ABC (with right angle C), angle A is five times greater than angle B. Find the angles of triangle ABC.

the sum of the angles in a right-angled triangle is 180 °. from this it follows that 180 ° -90 ° = 90 ° (this is the sum of the angles A and B) Let the angle B = x °, then the angle A = 5x °. make the equation:
x + 5x = 90
6x = 90
x = 90/6
x = 15 ° = angle B
well, to find the angle A, you need 15 * 5 = 75 °
answer: angle A = 75 °, angle B = 15 °, angle C = 90 °