IBEW Math Practice: Quadratics and Linear Functions

This practice set targets two algebra skills that commonly cause trouble:

• Quadratics: finding the factor pair, writing the factors, and setting each factor equal to zero.
• Functions and tables: determining whether a slope is positive or negative and identifying the $y$-intercept.

Try these without a calculator.

Part 1 — Quadratic Factoring

1. Solve

$x^2 - 11x + 24 = 0$

A. $x = -3, -8$
B. $x = 3, 8$
C. $x = -3, 8$
D. $x = 4, 6$

2. Solve

$x^2 + 9x + 20 = 0$

A. $x = 4, 5$
B. $x = -4, -5$
C. $x = -4, 5$
D. $x = 2, 10$

3. Solve

$x^2 - x - 12 = 0$

A. $x = 4, -3$
B. $x = -4, 3$
C. $x = 6, -2$
D. $x = -4, -3$

4. Solve

$x^2 + 2x - 15 = 0$

A. $x = -3, 5$
B. $x = 3, -5$
C. $x = -3, -5$
D. $x = 3, 5$

5. Solve

$x^2 - 16 = 0$

A. $x = 4$ only
B. $x = -4$ only
C. $x = 4, -4$
D. $x = 8, -2$

6. Solve

$2x^2 - 10x = 0$

A. $x = 0, 5$
B. $x = 0, -5$
C. $x = 2, 5$
D. $x = -2, 5$

7. Solve

$x^2 + 7x + 12 = 0$

A. $x = 3, 4$
B. $x = -3, -4$
C. $x = -3, 4$
D. $x = 2, 6$

8. Solve

$x^2 - 5x - 24 = 0$

A. $x = -8, 3$
B. $x = 8, -3$
C. $x = -8, -3$
D. $x = 6, -4$

For questions 1–8, use this process:

$\boxed{\text{factor pair} \rightarrow \text{write factors} \rightarrow \text{set each factor}=0}$

For example, $(x - 7)(x + 2) = 0$ means

$x - 7 = 0 \Rightarrow x = 7$

and

$x + 2 = 0 \Rightarrow x = -2.$

Part 2 — Function Tables and Slope Signs

9. Which equation fits the table?

$x$	$y$
$-2$	$11$
$-1$	$7$
$0$	$3$
$1$	$-1$

A. $y = 4x + 3$
B. $y = -4x + 3$
C. $y = -3x + 4$
D. $y = 4x - 3$

10. Which equation fits the table?

$x$	$y$
$0$	$-2$
$1$	$1$
$2$	$4$
$3$	$7$

A. $y = 3x - 2$
B. $y = -3x - 2$
C. $y = 2x + 3$
D. $y = 3x + 2$

11. Which equation fits the table?

$x$	$y$
$-1$	$-1$
$0$	$2$
$1$	$5$
$2$	$8$

A. $y = -3x + 2$
B. $y = 3x - 2$
C. $y = 3x + 2$
D. $y = 2x + 3$

12. Which equation fits the table?

$x$	$y$
$-2$	$-3$
$0$	$1$
$2$	$5$
$4$	$9$

A. $y = 2x + 1$
B. $y = -2x + 1$
C. $y = x + 2$
D. $y = 2x - 1$

13. A line passes through $(-2, 9)$ and $(1, 0)$. Which equation describes the line?

A. $y = 3x + 3$
B. $y = -3x + 3$
C. $y = -3x - 3$
D. $y = 3x - 3$

14. Which equation fits the table?

$x$	$y$
$-1$	$11$
$0$	$6$
$1$	$1$
$2$	$-4$

A. $y = 5x + 6$
B. $y = -5x + 6$
C. $y = -6x + 5$
D. $y = 5x - 6$

15. A line passes through $(0, -4)$ and $(2, 2)$. Which equation describes the line?

A. $y = -3x - 4$
B. $y = 3x + 4$
C. $y = 3x - 4$
D. $y = -3x + 4$

For questions 9–15, pay attention to direction:

$x \text{ goes right},\ y \text{ goes up} \Rightarrow \text{positive slope}$

$x \text{ goes right},\ y \text{ goes down} \Rightarrow \text{negative slope}$

When $x = 0$, the corresponding $y$-value is the $y$-intercept.