Here’s the hint.

Click me!

# Change in plans!

Due to the move-up of the 6 weeks test (don’t worry, you’ve already seen all the material it covers), the schedule is changing a bit this week and next.

I’ve also created a practice set on ck12. If you’re having trouble with solving equations, you should visit the site and get some practice this weekend. Otherwise, there is no homework this weekend! Hooray!

http://www.ck12.org/group-assignments/114113

# A little help with Transformations

Here’s a Geogebra book that will help you with Translations. I’ll add all the tools for transformations to it over the course of this week.

You may find pages 2 and 3 especially helpful in solving today’s challenge problem… What happens when the dilation factor, k, is negative in a dilation?

# Summary of Transformation Rules

Several of you have requested a summary of all the transformation rules…

Here you go! You may want to rewrite some of them to make more sense to you. I’ve also made these available as a Quizlet deck.

Translate a units right/left and b units up/down
$(x,y)\to (x+a,y+b)$

Reflect across the x-axis
$(x,y)\to (-x,y)$

Reflect across the y-axis
$(x,y)\to (x,-y)$

Rotate 90º clockwise about the origin
$(x,y)\to (y,-x)$

Rotate 90º counter-clockwise about the origin
$(x,y)\to (-y,x)$

$(x,y)\to (-x,-y)$

Dilation centered on the origin, scale factor of $k,\ k>0$
$(x,y)\to (kx,ky)$

You’ve also learned through your homework that a reflection across the line $y=x$ looks like
$(x,y)\to (y,x)$

# Today’s Function Activity

Some of you did not spend your time wisely during class today.

If you need to refer to the images from the handhelds to complete the handout, you may view them below.

If you lost the handout (or missed class today), I’ve attached it, too.

Growing Patterns

# Determining the Interest rate based on payments

During class today as we were working the problem of the day, several people proposed possible interest rates to go with the interest paid by Henrí in paying off his loan.

Using a calculator similar to the one we used on Friday, it is possible to determine the interest rate.

I like this calculator, but I’m sure there are plenty more to choose from. Plugging in our example of $274/month for 36 months returns an interest rate of 6.05% for a total interest cost of$864.00. Several suggested that you could simply divide $\frac{864}{9000}=9.6$%?

Why does an interest rate of 6.05% per year end up with a total cost of 9.6%? Why would it not be $.0605\cdot 3=18$%?

Ponder those questions for next time.

Remember to take a look at the rest of the exploration for 16.3 (page 453, green book) and get started on the homework, but the homework won’t be due until Thursday. I do expect you to complete the exploration before class on Wednesday.

$R=\frac{P\cdot i}{1-{{(1+i)}^{-n}}}$