2. WARM UP! Jan. 28, 2013

3. Question 1 a.Express 3.157 X 10 -4 in standard form. b.Write 2.35% as a decimal.

4. Question 2 A unit on the grid of the map of Memorial Park is 0.06 mile. Find the distance between the old oak tree at (-4, 1) and the ranger station at (4, -3).

5. Question 3 Find the slope of line that passes through point R(-3,4) and point S(5,2)

6. Dilations A dilation is a transformation that produces an image that is the same shape as the original, but is a different size. Dilation is a transformation in which each point of an object is moved along a straight line. The straight line is drawn from a fixed point called the centre of dilation. The distance the points move depends on the scale factor. In dilation, the centre of dilation is the only invariant point. Scale factor = If the scale factor is greater than 1, the image is an enlargement. If the scale factor is between 0 and 1, the image is a reduction. Example: The figure shows two similar triangles PQR and P’Q’R’.

7. Question 4 Dilations: In the movie, King Kong, Kong is 60 feet tall. If an average gorilla is 5 feet tall, what is the scale factor of this enlargement? If an average gorilla weighs 350 lbs, how much does Kong weigh?

8. Time is up!!! Trade and Grade!

9. ANSWERS 1. a. 0.0003157 b..0235 2. 8.94 miles 3. -1/4 4. Scale factor = 12 Weighs 4,200 pounds

10. Critical Thinking 1 Eggtra Special! What is one way to drop a raw egg five feet over a concrete floor (with no cushioning) without breaking the egg?

11. ANSWER Extra Height: Drop the egg from 10 feet, it will drop over five feet without breaking…...

12. Critical Thinking 2 Know When to Hold ‘Em: We’ve laid out three cards below. One of them is a Jack, which is just to the right of a three. A Jack is also just to the left of a Jack. A diamond is just to the right of a diamond, and a diamond is just to the left of a heart. What are the cards?

13. ANSWER From left to right: three of diamonds, Jack of Diamonds, Jack of Hearts