Squares, Cubes and Square Roots

- (5 min) Mental Math
- What is the probability of flipping a coin twice

and getting a 'heads' both times? [1/4] - Start with 2700, divide by 100, then divide by 3 [9]
- What is the probability of drawing a black 8

out of a deck of 52 cards? [1/26] - What is 30% of 90? [27]
- Multiply 1/3 by 3/4 and reduce [1/4]

- What is the probability of flipping a coin twice
- (5 min) Review of homework #18 (<= 3 problems)

- (10 min) Introduce squares,cubes and square roots:

- Pass out the "Squares, Cubes, and Square Roots" handout.
- Follow the discussion in the handout.
- Have students fill out the table on the first page of the handout.
- Follow the "Square Root" discussion on the second page of the handout.
- Have the students fill out the table on the second page of the handout.
- Show students the square root key on the calculator. Do a few simple square roots using this key.
- Discuss the solution of equations with squares:
Example 1: x ^{2}+ 4 = 20Solution: x = 4 Example 2: 40 - x ^{2}= 4Solution: x = 6 Example 3: 2x ^{2}- 1 = 17Solution: x = 3

- (Remainder of class) In-class Exercise.

- Hand out homework as students successfully complete the in-class exercise.

Note:
Students have a tendency to compute squares as multiplies by
2:^{2} = 5 x 2 = 10^{2} = 2 x 2 = 4 |