Answer:
13 and -14 satisfy this condition
Step-by-step explanation:
Let's represent that number as x
and the square of x is x^2
So,
x + x^2 = 182
Subtract 182 from both sides
x + x^2 - 182 = 182 - 182
x + x^2 - 182 = 0
rearrange the quadratic equation
x^2 + x -182 = 0
let's use the quadratic formula
or 
a = 1, b = 1, c = -182
or 
or 
or 
or 
or 
13 or - 14
Lets check
13 + 13^2 = 13 + 169
= 182
Also,
-14 + (-14^2) = -14 + 196
= 182
Number 12 what do you think we do first
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:
78 79 80
Step-by-step explanation:
Let the smallest number = x
Let the next number = x + 1
Let the largest number = x + 2
x + x + 1 + x + 2 = 237 Add together to get the equation
3x + 3 = 237 Subtract 3 from both sides.
3x + 3 - 3 = 237 - 3 Combine the right
3x = 234 Divide by 3
x = 234/3
x = 78
The smallest number is 78
The next number 79
The highest number is 80
Answer:
3/7
Step-by-step explanation:
There are 7 letters in ALABAMA. And there are 4 A's in ALABAMA. So if you're trying to not get an A then you would subtract 4 from 7. Which you would get 3/7 of the letters in ALABAMA are not A.
