I. Solve the following Quadratic Equation as indicated.
1. X² - 36 = 0. ] Extracting square
2. ( 4 - 5 )² = 25 ] Extracting square
3. 16 X² - 3x = 0 ] Factoring method
4. y² - y - 12 = 0. ] Factoring method
5. m² + 2m - 8 = 0. ] completing square
6. n² + 10n - 75 = 0. ] Completing square
7. X² + 6x + 5 = 0 ] Quadratic formula
8. X² - 2X + 1 = 0. ] Quadratic formula
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Verified answer
Answer:
Step-by-step explanation:
1. x² - 36 = 0
Transpose
x² = 36
Extract the square root
√x² = √36
x = 6
x = -6
2. (4-5)² = 25 ---------no variable unable to solve
3. 16x² - 3x = 0
Get the factors of the terms
x(16x -3) = 0
x = 0
16x - 3 = 0
16x = 3
x = 3/16
4. y² - y - 12 = 0
Factor
(y -4)(y + 3) = 0
y - 4 = 0
y = 4
y + 3 = 0
y = -3
5. m² + 2m - 8 = 0
m² + 2m + 1 - 8 -1 = 0
(m + 1)² - 9 = 0
(m + 1)² = 9
Get the square root for each side of the equation
√(m+1)² = √9
m + 1 = +-3
m + 1 = 3
m = 3 - 1
m = 2
m+1 = -3
m = -3 -1
m = -4
6. n² + 10n - 75 = 0
10/2 = 5
5²
n² + 10n +5² - 75 -5² = 0
(n +5)² - 75 - 25 = 0
(n +5)² = 75 +25
Get the square root
√(n+5)² = √100
n + 5 = +-10
n + 5 = 10
n = 10 -5
n = 5
n + 5 = -10
n = -10 - 5
n = -15
7. x² + 6x + 5 = 0
Use quadratic formula
[tex]x = \frac{-b (+-)\sqrt{b^2-4ac} }{2a}[/tex]
a = 1
b = 6
c = 5
[tex]x = \frac{-6(+-) \sqrt{6^2-4(1)(5)} }{2(1)} \\x = \frac{-6 (+-) \sqrt{36-20} }{2} \\x = \frac{-6(+-)\sqrt{16} }{2}\\ x = \frac{-6(+-)4}{2} \\x = \frac{-6+4}{2}\\ x = \frac{-2}{2} \\x = -1\\x = \frac{-6-4}{2}\\ x = \frac{-10}{2} \\x = -5\\[/tex]
x = -1
x = -5
8. x² - 2x + 1 = 0
a = 1
b = -2
c = 1
[tex]x = \frac{-(-2)(+-)\sqrt{(-2)^2 - 4(1_)1)} }{2(1)} \\x = \frac{2(+-)\sqrt{4-4} }{2} \\x = \frac{2}{2} \\x = 1[/tex]
x = 1