Answer: the man's claim is true.
Step-by-step explanation:
Given that 30% of the well find water at a depth <=100 feet
P(X<=100) = 0.30
If the man's prediction work well the probability of finding well at less than 100 or equal should be high fwhen calculated from his results. So give 27 out of 80 wells
P(X<=100) = 27/80
P(X<=100) = 0.3375
Since 0.3375 > 0.3
The man's claim is true.
Answer:
Step-by-step explanation:
I’m pretty sure that the one you marked is correct
Answer:
Perimeter will be = 21.6
Step-by-step explanation:
As we know the formula to get the length between two points A and B having coordinates A(x,y) and B (a,b) is
AB = √(x-a)²+(y-b)²
We will use this formula to get the lengths of all sides of the quadrilateral.
AB=√(4+3)²+(2-2)² =√7² =7
BC = √(3-4)²+(-3-2)²=√(-1)²+(-5)² = √1+25=√26 = 5.1
CD = √(3+3)²+(-3-3)² = √6²+(-6)² = √72 = 8.5
DA = √(-3+3)²+(3-2)² =√1 = 1
Since perimeter of the quadrilateral = sum of lengths of all sides
Perimeter = 7 + 5.1 + 8.5 + 1 = 21.6
Remember that the vertex form of a parabola or quadratic equation is:
y=a(x-h)^2+k, where (h,k) is the "vertex" which is the maximum or minimum point of the parabola (and a is half the acceleration of the of the function, but that is maybe too much :P)
In this case we are given that the vertex is (1,1) so we have:
y=a(x-1)^2+1, and then we are told that there is a point (0,-3) so we can say:
-3=a(0-1)^2+1
-3=a+1
-4=a so our complete equation in vertex form is:
y=-4(x-1)^2+1
Now you wish to know where the x-intercepts are. x-intercepts are when the graph touches the x-axis, ie, when y=0 so
0=-4(x-1)^2+1 add 4(x-1)^2 to both sides
4(x-1)^2=1 divide both sides by 4
(x-1)^2=1/4 take the square root of both sides
x-1=±√(1/4) which is equal to
x-1=±1/2 add 1 to both sides
x=1±1/2
So x=0.5 and 1.5, thus the x-intercept points are:
(0.5, 0) and (1.5, 0) or if you like fractions:
(1/2, 0) and (3/2, 0) :P
