Answer: she scored 69 points on the second test.
Step-by-step explanation:
Let x represent the number of points that she scored in the first test.
Let y represent the number of points that she scored in the second test.
If her mean score was 75, it means that
(x + y)/2 = 75
x + y = 75 × 2
x + y = 150- - - - - - - - - 1
If she scored 12 points more on the first test than the second test, it means that
x = y + 12
Substituting x = y + 12 into equation 1, it becomes
y + 12 + y = 150
2y + 12 = 150
2y = 150 - 12
2y = 138
y = 138/2
y = 69
Answer:
Step-by-step explanation:
The ladder forms a right angle triangle with the building and the ground. The length of the ladder represents the hypotenuse of the right angle triangle. The height, h from the top of the ladder to the base of the house represents the opposite side of the right angle triangle.
The distance from the foot of the ladder to the base of the house represents the adjacent side of the right angle triangle.
To determine the height, h that the ladder reaches, we would apply Pythagoras theorem which is expressed as
Hypotenuse² = opposite side² + adjacent side²
15² = 9² + h²
225 = 81 + h²
h² = 225 - 81 = 144
h = √144 = 12 feet