Enable contrast version

Tutor profile: Katy W.

Inactive
Katy W.
Previous Classroom & Online Teacher Math 6-12, College Statistics
Tutor Satisfaction Guarantee

Questions

Subject: Pre-Calculus

TutorMe
Question:

What conic section is described by the equation 9x^2 + 3x + 16y^2 + 4y = 8 ?

Inactive
Katy W.
Answer:

There are four conic sections: parabolas, circles, ellipses, and hyperbolas. To tell the difference by looking at the equations, we first investigate the degree of x and y. Both of our variables are squared, so we can rule out a parabola. In a circle, the coefficients of the squared terms must be the same number. Ours are different, so this is not a circle. In a hyperbola, the signs of the squared terms must be different. Ours are not different, so this is not a hyperbola. Therefore, this equation is an ellipse.

Subject: Statistics

TutorMe
Question:

A researcher evaluates 40 samples, which end up with a mean of 13 and a standard deviation of 1. Later, she discovers that her measurement tool was misaligned and all of her measurements were consistently too large by 2. How will this affect the sample mean and standard deviation?

Inactive
Katy W.
Answer:

While some students would like to try and calculate a new mean and standard deviation, that is unnecessary! If every data point was too large by 2, and we subtract 2 from each one, the mean will be 13 - 2 = 11. The standard deviation is a measure of spread, the variation in the data would not change if they are all consistently off by 2, so the standard deviation remains the same. In more mathematical sense, the mean is calculated by the sum of the observations divided by the number of observations. In this case, we know the sum of all the observations was originally 40*13. If we subtract 2 for all 40 observations and divide by the number of observations, we have (40*13 - 2*40) / 40, or 11.

Subject: Algebra

TutorMe
Question:

Where does the graph of y = x^2 + 3x - 10 cross the x-axis?

Inactive
Katy W.
Answer:

Graphs cross the x-axis where y=0, so we can say 0 = x^2 + 3x - 10 At this point, we can solve via the quadratic equation if we wanted to, but this one can also be solved by factoring. We need to find two numbers that multiply to make -10, but add to make 3. We know one has to be negative, and one positive in order to multiply to -10, and there are two possible integer pairs: 1 and 10 2 and 5 If we use +5 and -2, this will multiply to -10 and also add to 3, so we can factor it this way: 0 = (x+5)(x-2) We can now break this into x + 5 = 0 or x -2 = 0 x = -5 or x = 2 The graph of the equation will cross the x-axis at x=-5 and again at x=2.

Contact tutor

Send a message explaining your
needs and Katy will reply soon.
Contact Katy

Request lesson

Ready now? Request a lesson.
Start Lesson

FAQs

What is a lesson?
A lesson is virtual lesson space on our platform where you and a tutor can communicate. You'll have the option to communicate using video/audio as well as text chat. You can also upload documents, edit papers in real time and use our cutting-edge virtual whiteboard.
How do I begin a lesson?
If the tutor is currently online, you can click the "Start Lesson" button above. If they are offline, you can always send them a message to schedule a lesson.
Who are TutorMe tutors?
Many of our tutors are current college students or recent graduates of top-tier universities like MIT, Harvard and USC. TutorMe has thousands of top-quality tutors available to work with you.
BEST IN CLASS SINCE 2015
TutorMe homepage
Made in California by Zovio
© 2020 TutorMe, LLC
High Contrast Mode
On
Off