Answer:
The ladder reaches a height of 6 m.
Step-by-step explanation:
Given that,
Height of the ladder, H = 6.5 m
The foot of the ladder is 2.5 m from the foot of the wall.
We need to find the height does the ladder reach. If we consider a triangle in which hypotenuse is 6.5 m, foot of the ladder is 2.5 m then we need to find the height of the ladder i.e.

The ladder reaches a height of 6 m.
Answer: f(x) = -0.016x² + 1.6x
Step-by-step explanation:
If the lenght of the road over the arch is 100m, we can consider a coordinate plane and say that the road starts at point (0,0) and finishes at (100,0). The vertice of the parabola is at point (50,40), because the maximum height is 40 and it is always in the middle point of the roots.
So, we have
(0,0) (50,40) (100,0)
A quadratic function is always on the form: f(x) = ax² + bx + c
0 = a0² + b0 + c
40 = a50² + b50 + c
0 = a100² + b100 + c
0 = a0² + b0 + c → c = 0 ∴
40 = a50² + b50
0 = a100² + b100
_________________________
2500a + 50b = 40 (*2)
10000a + 100b = 0
_________________________
5000a + 100b = 80
10000a + 100b = 0 (-)
__________________________
-5000a = 80
-a=80/5000
a=-0.016
∴
2500a + 50b = 40
2500.(-0.016) + 50b = 40
-40 + 50b = 40
50b = 80
b = 80/50
b = 1.6
This way f(x) = -0.016x² + 1.6x
Answer:
6x-2
Step-by-step explanation:
-4x(1-3)-(2x+2)
= 4x+12x-2x-2
6x-2
(simplify)