Answer:
Your answer would be
2(13+9x)
Step-by-step explanation:
Answer:
Option A
Step-by-step explanation:
Given expression:
<u>Option A</u>
⇒ (x - 4)(3x + 2)
⇒ (x × 3x) + (2 × x) + (-4 × 3x) + (-4 × 2)
⇒ (3x²) + (2x) + (-12x) + (-8)
⇒ 3x² + 2x - 12x - 8
⇒ 3x² - 10x - 8
3x² - 10x - 8 = 3x² - 10x - 8 (Yes!)
<u>Option B</u>
⇒ (3x - 4)(x - 2)
⇒ (3x × x) + (3x × -2) + (-4 × x) + (-4 × -2)
⇒ (3x²) + (-6x) + (-4x) + (8)
⇒ 3x² - 6x - 4x + (8)
⇒ 3x² - 10x + 8
3x² - 10x - 8 = 3x² - 10x + 8 (No!)
<u>Option C</u>
⇒ (3x - 4)(x + 2)
⇒ (3x × x) + (3x × 2) + (-4 × x) + (-4 × 2)
⇒ (3x²) + (6x) + (-4x) + (-8)
⇒ 3x² + 6x - 4x - 8
⇒ 3x² + 2x - 8
3x² - 10x - 8 = 3x² + 2x - 8 (No!)
<u>Option D</u>
⇒ (3x - 2)(x - 4)
⇒ (3x × x) + (3x × -4) + (-2 × x) + (-2 × -4)
⇒ (3x²) + (-12x) + (-2x) + (8)
⇒ 3x² - 12x - 2x + 8
⇒ 3x² - 14x + 8
3x² - 10x - 8 = 3x² - 14x + 8 (No!)
Since the expression of option A has the same value as the given expression, option A is correct.
Answer:
9.6
Step-by-step explanation:
Answer:
x = ± 2, x = 3
Step-by-step explanation:
note that x = 2 gives
2³ - 3(2)² - 4(2) + 12 = 8 - 12 - 8 + 12 = 0
Hence x = 2 is a root and (x - 2) is a factor
x³ - 3x² - 4x + 12 ÷ (x - 2)
= (x - 2)(x² - x - 6)
= (x - 2)(x + 2)(x - 3), hence
(x - 2)(x + 2)(x - 3) = 0
equate each factor to zero and solve for x
x - 2 = 0 ⇒ x = 2
x + 2 = 0 ⇒ x = - 2
x - 3 = 0 ⇒ x = 3
