1. Solve for $x$ in the equation $x - 5 = -8$.
$$x - 5 = -8$$
Add 5 to both sides:
$$x - 5 + 5 = -8 + 5$$
$$x = -3$$
2. Evaluate $(x^2 - 5)(x^{-3} - x)$ at $x = -3$.
Calculate each part:
$$x^2 - 5 = (-3)^2 - 5 = 9 - 5 = 4$$
$$x^{-3} - x = (-3)^{-3} - (-3) = \frac{1}{(-3)^3} + 3 = \frac{1}{-27} + 3 = -\frac{1}{27} + 3 = \frac{-1 + 81}{27} = \frac{80}{27}$$
Multiply:
$$(x^2 - 5)(x^{-3} - x) = 4 \times \frac{80}{27} = \frac{320}{27}$$
3. Factor and simplify each quadratic:
4. $x^2 + 6x - 16$
Try factors of -16 that sum to 6: 8 and -2.
$$x^2 + 6x - 16 = (x + 8)(x - 2)$$
5. $x^2 - 6x + 9$
Try factors of 9 that sum to -6: -3 and -3.
$$x^2 - 6x + 9 = (x - 3)^2$$
6. $x^2 - 6x - 27$
Try factors of -27 that sum to -6: -9 and 3.
$$x^2 - 6x - 27 = (x - 9)(x + 3)$$
7. $p^2 - p - 20$
Factors of -20 that sum to -1: -5 and 4.
$$p^2 - p - 20 = (p - 5)(p + 4)$$
8. $x^2 - 2x - 15$
Factors of -15 that sum to -2: -5 and 3.
$$x^2 - 2x - 15 = (x - 5)(x + 3)$$
9. $p^2 - 4p - 21$
Factors of -21 that sum to -4: -7 and 3.
$$p^2 - 4p - 21 = (p - 7)(p + 3)$$
10. $p^2 + p - 20$
Factors of -20 that sum to 1: 5 and -4.
$$p^2 + p - 20 = (p + 5)(p - 4)$$
11. $k^2 - 3k - 40$
Factors of -40 that sum to -3: -8 and 5.
$$k^2 - 3k - 40 = (k - 8)(k + 5)$$
12. $m^2 + 9m + 20$
Factors of 20 that sum to 9: 5 and 4.
$$m^2 + 9m + 20 = (m + 5)(m + 4)$$
13. $x^2 + 33 + 14x$
Rewrite as $x^2 + 14x + 33$.
Factors of 33 that sum to 14: 11 and 3.
$$x^2 + 14x + 33 = (x + 11)(x + 3)$$
14. $-13p + p^2 + 36$
Rewrite as $p^2 - 13p + 36$.
Factors of 36 that sum to -13: -9 and -4.
$$p^2 - 13p + 36 = (p - 9)(p - 4)$$
15. $-30 + m^2 - m$
Rewrite as $m^2 - m - 30$.
Factors of -30 that sum to -1: -6 and 5.
$$m^2 - m - 30 = (m - 6)(m + 5)$$
16. $11n + n^2 + 18$
Rewrite as $n^2 + 11n + 18$.
Factors of 18 that sum to 11: 9 and 2.
$$n^2 + 11n + 18 = (n + 9)(n + 2)$$
17. $x^2 + 27 + 12x$
Rewrite as $x^2 + 12x + 27$.
Factors of 27 that sum to 12: 9 and 3.
$$x^2 + 12x + 27 = (x + 9)(x + 3)$$
18. $x^2 + 90 - 19x$
Rewrite as $x^2 - 19x + 90$.
Factors of 90 that sum to -19: -10 and -9.
$$x^2 - 19x + 90 = (x - 10)(x - 9)$$
19. $x^2 + x - 132$
Factors of -132 that sum to 1: 12 and -11.
$$x^2 + x - 132 = (x + 12)(x - 11)$$
20. $a^2 + 90 - 47a$
Rewrite as $a^2 - 47a + 90$.
Factors of 90 that sum to -47: -45 and -2.
$$a^2 - 47a + 90 = (a - 45)(a - 2)$$
21. $10m + m^2 + 16$
Rewrite as $m^2 + 10m + 16$.
Factors of 16 that sum to 10: 8 and 2.
$$m^2 + 10m + 16 = (m + 8)(m + 2)$$
22. Solve system:
$$\begin{cases} 3x + y = 9 \\ x - 4y = -10 \end{cases}$$
Multiply second by 3:
$$3x - 12y = -30$$
Subtract first:
$$(3x - 12y) - (3x + y) = -30 - 9$$
$$-13y = -39$$
$$y = 3$$
Substitute $y=3$ into $3x + y = 9$:
$$3x + 3 = 9$$
$$3x = 6$$
$$x = 2$$
23. Solve system:
$$\begin{cases} 2x + 5y = 7 \\ x + 3y = 4 \end{cases}$$
Multiply second by 2:
$$2x + 6y = 8$$
Subtract first:
$$(2x + 6y) - (2x + 5y) = 8 - 7$$
$$y = 1$$
Substitute $y=1$ into $x + 3y = 4$:
$$x + 3 = 4$$
$$x = 1$$
24. Solve system:
$$\begin{cases} 3x + 4y = -7 \\ 3x - 3y = 21 \end{cases}$$
Subtract second from first:
$$(3x + 4y) - (3x - 3y) = -7 - 21$$
$$7y = -28$$
$$y = -4$$
Substitute $y=-4$ into $3x + 4y = -7$:
$$3x + 4(-4) = -7$$
$$3x - 16 = -7$$
$$3x = 9$$
$$x = 3$$
25. Solve system:
$$\begin{cases} 2x - 2y = -2 \\ 4x - 5y = -9 \end{cases}$$
Multiply first by 2:
$$4x - 4y = -4$$
Subtract from second:
$$(4x - 5y) - (4x - 4y) = -9 - (-4)$$
$$-y = -5$$
$$y = 5$$
Substitute $y=5$ into $2x - 2y = -2$:
$$2x - 2(5) = -2$$
$$2x - 10 = -2$$
$$2x = 8$$
$$x = 4$$
26. Simplify $7\sqrt{20} - 5\sqrt{32}$.
$$\sqrt{20} = \sqrt{4 \times 5} = 2\sqrt{5}$$
$$\sqrt{32} = \sqrt{16 \times 2} = 4\sqrt{2}$$
Substitute:
$$7 \times 2\sqrt{5} - 5 \times 4\sqrt{2} = 14\sqrt{5} - 20\sqrt{2}$$
27. Simplify $2\sqrt{18} - 5\sqrt{8} + 4\sqrt{50}$.
$$\sqrt{18} = \sqrt{9 \times 2} = 3\sqrt{2}$$
$$\sqrt{8} = \sqrt{4 \times 2} = 2\sqrt{2}$$
$$\sqrt{50} = \sqrt{25 \times 2} = 5\sqrt{2}$$
Substitute:
$$2 \times 3\sqrt{2} - 5 \times 2\sqrt{2} + 4 \times 5\sqrt{2} = 6\sqrt{2} - 10\sqrt{2} + 20\sqrt{2}$$
Combine:
$$(6 - 10 + 20)\sqrt{2} = 16\sqrt{2}$$
28. Simplify $\frac{1 + \frac{1}{y}}{\frac{1}{y}}$.
Rewrite numerator:
$$1 + \frac{1}{y} = \frac{y}{y} + \frac{1}{y} = \frac{y + 1}{y}$$
Divide:
$$\frac{\frac{y + 1}{y}}{\frac{1}{y}} = \frac{y + 1}{y} \times \frac{y}{1} = y + 1$$
29. Simplify $\frac{\frac{a}{b} - 4}{\frac{x}{b} - b}$.
Rewrite denominator:
$$\frac{x}{b} - b = \frac{x}{b} - \frac{b^2}{b} = \frac{x - b^2}{b}$$
Rewrite numerator:
$$\frac{a}{b} - 4 = \frac{a}{b} - \frac{4b}{b} = \frac{a - 4b}{b}$$
Divide:
$$\frac{\frac{a - 4b}{b}}{\frac{x - b^2}{b}} = \frac{a - 4b}{b} \times \frac{b}{x - b^2} = \frac{a - 4b}{x - b^2}$$
30. Simplify $\frac{\frac{a}{x} - a}{x + \frac{y}{x}}$.
Rewrite numerator:
$$\frac{a}{x} - a = \frac{a}{x} - \frac{ax}{x} = \frac{a - ax}{x} = \frac{a(1 - x)}{x}$$
Rewrite denominator:
$$x + \frac{y}{x} = \frac{x^2}{x} + \frac{y}{x} = \frac{x^2 + y}{x}$$
Divide:
$$\frac{\frac{a(1 - x)}{x}}{\frac{x^2 + y}{x}} = \frac{a(1 - x)}{x} \times \frac{x}{x^2 + y} = \frac{a(1 - x)}{x^2 + y}$$
Algebra Problems 4D7Bfb
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