Question

question 6

simplify: \\(-\left(2x^2 - 9\
ight)\\)

\\(\bigcirc -2x^2 - 9\\)
\\(\bigcirc -2x^2 + 9\\)
\\(\bigcirc 2x^2 + 9\\)
\\(\bigcirc -7x^2\\)

question 7

add the following polynomials: \\(\left(3x^4 - 2x^2 + 7\
ight) + \left(2x^3 + 8x^2 + x + 11\
ight)\\)

\\(\bigcirc 3x^4 + 2x^3 + 6x^2 + x + 18\\)
\\(\bigcirc 5x^4 + 6x^2 + x + 18\\)
\\(\bigcirc 3x^4 + 2x^3 + 10x^2 + x + 18\\)
\\(\bigcirc 3x^4 + 8x^2 + x + 11\\)

Explanation:

Distribute the negative sign

Using the Distributive Property with Negative Sign knowledge point

$$ -(2x^2 - 9) = -1 \cdot (2x^2) - 1 \cdot (-9) = -2x^2 + 9 $$

Group like terms for addition

Using the Polynomial Addition and Combining Like Terms knowledge points

$$
LATEXBLOCK0
$$

Combine the coefficients

Using the Combining Like Terms knowledge point

$$
LATEXBLOCK1
$$

Answer:

Question 6

• (A) \(-2x^2 - 9\)
• (B) \(-2x^2 + 9\) (Correct answer)
• (C) \(2x^2 + 9\)
• (D) \(-7x^2\)

Question 7

• (A) \(3x^4 + 2x^3 + 6x^2 + x + 18\) (Correct answer)
• (B) \(5x^4 + 6x^2 + x + 18\)
• (C) \(3x^4 + 2x^3 + 10x^2 + x + 18\)
• (D) \(3x^4 + 8x^2 + x + 11\)