8.6 Solving Quadratics by Square Roots

Solve using square roots:

3x² - 1 = 11

• x = 12

• x = 4

• x = 2

• x = -2, 2

Solve using square roots:

2x² = 48

• x = 24

• x = 4√6

• x = 2√6

• x = ±2√6

Solve using square roots:

(x - 1)² = 16

• x = 17

• x = ±6

• x = -3, 5

• x = 5

Solve using square roots:

25x² - 95 = 49

• x = ±144/25

• x =±√(46)/5

• x = ±12/5

• x = ±5/12

Solve using square roots:

2(x + 2)² - 16 = 80

• x = -2 ± √48

• x = ± 8√3

• x = -6√3, 2√3

• x = -2 ± 4√3

• x = ± 2√3

Solve using square roots:

5x² = 1

• x = 1/5

• x = ±√(5)/5

• x = ±1/5

• x = ± 1

Solve using square roots:

2x² + 15 = 9

• x = ±2√6

• x = ±√3

• x = -√3

• no solution

Solve for x

x² = 64

• x = 8, -8

• x = 32, -32

• x = 4, -4

• No real solution

Solve using square roots.
k² - 6 = 43

• k = √37
• k = 37 or - 37
• k = 7, k = -7
• no solution

Solve using square roots.
5b² - 4 = 41

• b = 9, b = -9
• b = 3, b = -3
• b = 8, b = -8
• no solution