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Please I need help I need it under 20min​

Please I need help I need it under 20min​-example-1
User Yunnosch
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1 Answer

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12 votes

Answer:

See below ~

Explanation:

Solving :

(a) Coordinates of P and Q

⇒ Equate the lines' equations

⇒ 2x² - 6x - 8 = 2x - 14

⇒ 2x² - 8x + 6 = 0

⇒ x² - 4x + 3 = 0

⇒ (x - 3)(x - 1) = 0

x = 3 and x = 1

Substitute each x-value in the any of the 2 equations :

⇒ y = 2(3) - 14

⇒ y = 6 - 14

⇒ y = -8

P = (3, -8)

⇒ y = 2(1) - 14

⇒ y = 2 - 14

⇒ y = -12

Q = (1, -12)

(b)

(i) 2x² - 6x - 8 = 0

⇒ x² - 3x - 4 = 0

⇒ (x - 4)(x + 1) = 0

x = 4 and x = -1

(ii) 2x² - 6x = -4

⇒ 2x² - 6x + 4 = 0

⇒ x² - 3x + 2 = 0

⇒ (x - 1)(x - 2) = 0

x = 1 and x = 2

(c) Line of symmetry

Finding the vertex :

⇒ Vertex = (h, k)

⇒ h = -b/2a

⇒ h = -(-6)/2(2)

⇒ h = 6/4

⇒ h = 1.5

⇒ The axis of symmetry's equation is : x = 1.5

(d)

⇒ As the mentioned function is a quadratic function, irrational values such as √2, √3, √6, etc. cannot be taken into consideration

User Roboneter
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