2.13 use square roots to solve quadratics example 1 solve quadratic equations solution write...

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2.1 3 Use Square Roots to Solve Quadratics Example 1 Solve quadratic equations Solve quadratic equations Soluti on Write original equation. 5 ___ 2 z 9 9 4 5 a. 2 z 4 7 b. 2 r Solve the equation. 4 5 a. 2 z Add __ to each side. ____ z Take sq root of each side. Simplify. ____ z 3 The solutions are ____ and ____. 3 3

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2.13 Use Square Roots to Solve Quadratics

Example 1 Solve quadratic equationsSolve quadratic equations

Solution

Write original equation.

5___2 z 9

9

45 a. 2 z 47 b. 2 rSolve the equation.

45 a. 2 zAdd __ to each side.

____z Take sq root of each side.

Simplify.____z 3The solutions are ____ and ____.3 3

2.13 Use Square Roots to Solve Quadratics

Example 1 Solve quadratic equationsSolve quadratic equations

Solution

Write original equation.

7___2 r 3

45 a. 2 z 47 b. 2 rSolve the equation.

47 b. 2 rSubtract __ from each side.

Negative real numbers do not have real ____________.square roots

So, there is ____________.no solution

2.13 Use Square Roots to Solve Quadratics

Example 2 Take square root of a fractionTake square root of a fraction

SolutionWrite original equation.

25_______

2 k25

9

25

9

Solve the equation 25k 2 = 9.

925 2 k

Divide each side by ____.

__________

k Take sq root of each side.

Simplify._______

k5

3

The solutions are ____

and ____

.5

3

5

3

2.13 Use Square Roots to Solve QuadraticsCheckpoint. Solve the equation. Checkpoint. Solve the equation.

1083 .1 2 x3 3

2x 36x 36 6

1717 .2 2 t

2t 0t 0 0

17 17

2.13 Use Square Roots to Solve QuadraticsCheckpoint. Solve the equation. Checkpoint. Solve the equation.

418 .3 2 p81 81

2p81

4

p81

4

9

2

___2 x

2.13 Use Square Roots to Solve Quadratics

Example 3 Approximate solutions of a quadratic equationApproximate solutions of a quadratic equation

Solution

Write original equation.

3___4 2 x 205

2334 2 xSubtract __ from each side

Divide each side by ___.

Take sq roots of each side.____x 5

The solutions are ______ and _____.24.2 24.2

Solve 4x 2 + 3 = 23. Round the solution to the nearest hundredth.

4

Use a calculator. Round to the nearest hundredth.____x 24.2

2.13 Use Square Roots to Solve QuadraticsCheckpoint. Solve the equation. Round the solutions to Checkpoint. Solve the equation. Round the solutions to the nearest hundredth.the nearest hundredth.

2 22x 8x 8 83.2

972 .4 2 x

22x 167 7

2.13 Use Square Roots to Solve QuadraticsCheckpoint. Solve the equation. Round the solutions to Checkpoint. Solve the equation. Round the solutions to the nearest hundredth.the nearest hundredth.

6 62g 3g 3 .731

1916 .5 2 g

26g 181 1

_____ _______ are solutions The

____1x

2.13 Use Square Roots to Solve Quadratics

Example 4 Solve a quadratic equationSolve a quadratic equation

Solution

Write original equation.

___1 2 x 6

3015 2 xDivide each side by ___.

Take sq roots of each side.

_____x6

61 45.1

Solve 5(x + 1) 2 = 30. Round the solution to the nearest hundredth.

5

Subtract __ from each side61 1

_____. _______ and 61 45.3

1243 .6 2 m

2.13 Use Square Roots to Solve QuadraticsCheckpoint. Solve the equation. Round the solutions to Checkpoint. Solve the equation. Round the solutions to the nearest hundredth, if necessary.the nearest hundredth, if necessary.

3 3

4m 4

m 24

24m 4

4 4

m ,6 2

3234 .7 2 a

2.13 Use Square Roots to Solve QuadraticsCheckpoint. Solve the equation. Round the solutions to Checkpoint. Solve the equation. Round the solutions to the nearest hundredth, if necessary.the nearest hundredth, if necessary.

4 4

3a 8

a 83

23a 8

3 3

a ,83.5 17.0

2.13 Use Square Roots to Solve Quadratics

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