1. Square Roots and Radicals
Chapter 9 Review
Square Roots and Radicals

2. Try some:
Simplify these:

3. More examples:

4. How would you solve the equation: x2 = 4 (take the square root of each side!)
* Remember, the square root of a positive # has 2 answers! (one + and one -)

5. Solving Quadratic Equations
Solve x2 = -9
-5x2 = -12
x2 =
Solve. 3(x-2)2=21
(x-2)2 = 7

6. More Examples!
4. Solve.
Solve. 4x2-6=42
+6 +6
4x2=48
x2 = 12

7. Rationalizing the Denominator
You CANNOT leave a radical in the denominator of a fraction!
No tents in the basement!!!!
(the numerator is OK)
Just multiply the top & bottom of the fraction by the radical to “rationalize” the denominator.

8. Properties of Square Roots
(a>0 and b>0)
Product Property –
Quotient Property-
Example:
Example:

19. Simplify each expression.
Find a perfect square factor of 32.
Product Property of Square Roots B.
Quotient Property of Square Roots

20. Simplify each expression.
Product Property of Square Roots D.
Quotient Property of Square Roots

21. Simplify each expression.
Find a perfect square factor of 48.
Product Property of Square Roots F.
Quotient Property of Square Roots
Simplify.

22. Simplify each expression.G.
Product Property of Square Roots H.
Quotient Property of Square Roots

23. Examples 1. 2. 3.

24. Can’t have a tent in the basement!
More Examples! 1. 2.
Can’t have a tent in the basement!

25. Simplify by rationalizing the denominator.
Multiply by a form of 1.
= 2

26. Simplify the expression.
Multiply by a form of 1.

27. Simplify by rationalizing the denominator.
Multiply by a form of 1.

28. Simplify by rationalizing the denominator.
Multiply by a form of 1.

29. Simplify each expression.
1. Estimate to the nearest tenth.
6.7
Simplify each expression. 2. 3. 4. 5.

30. Solving Quadratic Equations using the Quadratic Formula
General equation of a quadratic:
You must get equation equal to zero before you determine a, b, and c.
Quadratic Formula:
Notice where the letters come from for the formula
We use the quadratic formula when something can not be factored. However, it also works for factorable quadratic equations as well.

31. Solve.
Ex. 1

32. Solve.
Ex. 2

33. Solve.
Ex. 3

34. Solve.
Ex. 4

35. What does the x-axis stand for?
Suppose a football player kicks a ball and gives it an initial upward velocity of 47ft/s. The starting height of the football is 3ft. If no one catches the football, how long will it be in the air?
Ex. 5
NOTE: For your homework tomorrow night, DO NOT answer the question. I want you to draw a sketch of what you think this picture would look like on a graph. Tell me what the x-axis symbolizes, what the y-axis symbolizes, and what the zeros represent in the problem.
What does the x-axis stand for?
What does the y-axis stand for?
What do the zeros represent?
Time the ball is in the air
Height of the ball
The amount of time it takes the ball to hit the ground.

36. Before you can find a,b, and c, you must get equation = to 0.
Type what is under the radical exactly as written on your calculator.
Simplify the radical
Divide by the denominator, if you can
Roots:

37. Divide by the denominator, if you can. Since I can’t, divide by GCF
Solve the quadratic equation by using the quadratic formula and leave answers in simplest radical form.
Simplify the radical
Divide by the denominator, if you can. Since I can’t, divide by GCF
Roots:

38. Solve the quadratic equation by using the quadratic formula and round answers to the nearest tenth.
Since we are solving to the nearest tenth, we do not need to simplify the radical!
Be careful when typing this into your calculator. I recommend that you type in the numerator then hit enter, then divide by denominator!
Roots:

39. Solve the quadratic equation by using the quadratic formula and round answers to the nearest tenth.
Roots:

40. Solve the quadratic equation by using the quadratic formula and round answers to the nearest tenth.
Roots

41. Divide by the denominator, if you can. Since I can’t, divide by GCF
Solve the quadratic equation by using the quadratic formula and leave answers in simplest radical form.
Roots:
Divide by the denominator, if you can. Since I can’t, divide by GCF