Answer:
58
Step-by-step explanation:
The midsegment has a length that is the average of the lengths of the parallel sides it is halfway between.
... LM = (38 +78)/2 = 116/2 = 58
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 rule is it subtracts 280 every time....!!!
HOPE I HELPED!!!!!!!
Answer:
x = -5, 1
Step-by-step explanation:
To factor an equation, break the polynomial into two binomials which multiply to make it. Find two numbers that multiply to C and add to B from .
-1 and 5 multiply to -5 and add to 4.
The zeros are the factors set equal to 0 and solved.
(x+5) = 0
x=-5
(x-1) = 0
x=1