Question

grade 9 math pop quiz (term 2 sample)
section 1: algebra basics & equations (10 marks)

1. solve for x: $3(x - 2) = 15$
2. simplify: $5x^2 + 2x - 3x^2 + 7$
3. what is the constant term in $2x^2 + 9x + 4?$
4. factor the expression: $x^2 - 9$
5. is $x^2 + 2x + 1$ a quadratic equation? (yes/no).

section 2: r

Explanation:

Step1: Divide both sides by 3

$\frac{3(x-2)}{3} = \frac{15}{3}$
$x-2 = 5$

Step2: Add 2 to both sides

$x-2+2 = 5+2$
$x = 7$

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Step1: Combine like $x^2$ terms

$5x^2 - 3x^2 + 2x + 7$
$2x^2 + 2x + 7$

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Step1: Identify constant term

The constant term is the term without a variable, so it is 4.

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Step1: Recognize difference of squares

$x^2 - 9 = x^2 - 3^2$

Step2: Apply difference of squares rule

$a^2 - b^2 = (a-b)(a+b)$, so $x^2 - 3^2 = (x-3)(x+3)$

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Step1: Define quadratic equation

A quadratic equation has the form $ax^2+bx+c=0$ (with $a
eq0$). The given expression is not set equal to a value, so it is an expression, not an equation.

Answer:

1. $x=7$
2. $2x^2 + 2x + 7$
3. $4$
4. $(x-3)(x+3)$
5. No