Answer:
height of the wall = 9.79 m
Explanation:
This form a right angled triangle.
Hypotenuse = length of the ladder = 10 m
Base = length from foot of ladder to wall.
Altitude = height of the wall
Pythagorean's theorem,
base² + altitude² = hypotenuse²
2² + altitude² = 10²
4 + altitude² = 100
altitude² = 100 - 4
altitude² = 96
altitude = √96 = 9.79 m