Step-by-step explanation:
so the smallest angle is angle A which is 30 degree
OK, so the graph is a parabola, with points x=0,y=0; x=6,y=-9; and x=12,y=0
Because the roots of the equation are 0 and 12, we know the formula is therefore of the form
y = ax(x - 12), for some a
So put in x = 6
-9 = 6a(-6)
9 = 36a
a = 1/4
So the parabola has a curve y = x(x-12) / 4, which can also be written y = 0.25x² - 3x
The gradient of this is dy/dx = 0.5x - 3
The key property of a parabolic dish is that it focuses radio waves travelling parallel to the y axis to a single point. So we should arrive at the same focal point no matter what point we chose to look at. So we can pick any point we like - e.g. the point x = 4, y = -8
Gradient of the parabolic mirror at x = 4 is -1
So the gradient of the normal to the mirror at x = 4 is therefore 1.
Radio waves initially travelling vertically downwards are reflected about the normal - which has a gradient of 1, so they're reflected so that they are travelling horizontally. So they arrive parallel to the y axis, and leave parallel to the x axis.
So the focal point is at y = -8, i.e. 1 metre above the back of the dish.
Answer:
The probability that Kyle will pick a girl who likes football is 12.5%.
Step-by-step explanation:
The data provided is as follows:
Boys Girls Total
Basketball 10 8 18
Football 25 7 32
Soccer 9 19 28
Baseball 18 22 40
Total 62 56 118
Compute the probability that Kyle will pick a girl who likes football as follows:
Thus, the probability that Kyle will pick a girl who likes football is 12.5%.
9514 1404 393
Answer:
26.4% decrease
Step-by-step explanation:
The amount of change is ...
2500 -1840 = -660
As a percentage of the original price, that is ...
-660/2500 × 100% = -26.4% . . . . . negative change = decrease
The decrease is 26.4%.
Answer:
5) a
6) a
7) b
8) d
9) a
10) b
11) c
12) a
Step-by-step explanation:
When it asks for range it is asking for the y values so when you plug in numbers such as 0,1,2 into the equation the y values you get are {0,90,180..}
Overall slope can be found by taking the x and y values of the two given points.
((y value of the second point)-(y value of the first point))/((x value of the second point)-(x value of the first point))
Using (1,2) and (-2, 5) you can do this by plugin in the numbers (5-2)/(-2-1)
So the slope will be 3/-3 = -1
Once you find the slope you can use this to find the equation of a line by pluging in values into y=mx + b
m = slope
y = use this from the points given
x = use this from the points given
