Answer:
Step-by-step explanation:
Given:
Focus point = (-5, -4)
Vertex point = (-5, -3)
We need to find the equation for the parabola.
Solution:
Since the x-coordinates of the vertex and focus are the same,
so this is a regular vertical parabola, where the x part is squared. Since the vertex is above the focus, this is a right-side down parabola and p is negative.
The vertex of this parabola is at (h, k) and the focus is at (h, k + p). So, directrix is y = k - p.
Substitute y = -4 and k = -3.
So the standard form of the parabola is written as.
Substitute vertex (h, k) = (-5, -3) and p = -1 in the above standard form of the parabola.
So the standard form of the parabola is written as.
Therefore, equation for the parabola with focus at (-5,-4) and vertex at (-5,-3)
Answer: -10,4
Step-by-step explanation:
y2-y1
x2-x1
Answer:
The smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income is 48.
Step-by-step explanation:
The complete question is:
The mean salary of people living in a certain city is $37,500 with a standard deviation of $2,103. A sample of n people will be selected at random from those living in the city. Find the smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income. Round your answer up to the next largest whole number.
Solution:
The (1 - <em>α</em>)% confidence interval for population mean is:
The margin of error for this interval is:
The critical value of <em>z</em> for 90% confidence level is:
<em>z</em> = 1.645
Compute the required sample size as follows:
Thus, the smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income is 48.
Answer:
AC = XY
Step-by-step explanation:
A triangle is a polygon with three sides and three angles. The types of triangles are scalene triangle, equilateral triangle, right angled triangle and obtuse triangle.
Two triangles are said to be congruent if all the three sides and three angles of one triangle is equal to the three sides and three angles of the other triangle.
In Δ ABC and ΔXYZ ,∠B=∠X=90. This means that triangle ABC and triangle XYZ are right angled triangle since one of their angles is 90 degrees.
The hypotenuse is the side opposite to right angle (90 degrees).
Therefore AC is the hypotenuse of triangle ABC and YZ is the hypotenuse of triangle XYZ.
If the hypotenuse and one leg of a right angled triangle is equal to the hypotenuse and leg of another right angled triangle, then the two triangles are congruent by RHS rule.
Since BC = XY, for Δ ABC congruent to ΔXYZ by R.H.S condition, the hypotenuse have to be equal, i.e. AC = XY
The answer to this question is 4