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
The slope-intercept form:
y = mx + b
m - slope
b - y-intercept
Answer:
B. y = 4/9x + 4
slope = 4/9, y-intercept = 4
D. y = -4/9x - 4
slope = -4/9, y-intercept = -4
-7 and positive 6. if you multiply a negative by a positive it will always be a negative.
Answer:
what are the choices
Step-by-step explanation:
P=3 and p=-1
First you subtract the number without a variable to the other side, so subtract one from seven, and subtract five from eight. After that just divide to make p by its self and you get the answer!!