Algebra Problems
1. Solve the equation: $$\frac{m}{2} + \frac{m}{3} + 3 = 2 + \frac{m}{6}$$
Step 1: Find a common denominator for the fractions on the left side. The denominators are 2, 3, and 6. The least common denominator (LCD) is 6.
Step 2: Rewrite each fraction with denominator 6:
$$\frac{m}{2} = \frac{3m}{6}, \quad \frac{m}{3} = \frac{2m}{6}$$
Step 3: Substitute back into the equation:
$$\frac{3m}{6} + \frac{2m}{6} + 3 = 2 + \frac{m}{6}$$
Step 4: Combine like terms:
$$\frac{5m}{6} + 3 = 2 + \frac{m}{6}$$
Step 5: Subtract $$\frac{m}{6}$$ from both sides:
$$\frac{5m}{6} - \frac{m}{6} + 3 = 2$$
Simplify:
$$\frac{4m}{6} + 3 = 2$$
Step 6: Simplify fraction:
$$\frac{2m}{3} + 3 = 2$$
Step 7: Subtract 3 from both sides:
$$\frac{2m}{3} = -1$$
Step 8: Multiply both sides by $$\frac{3}{2}$$:
$$m = -1 \times \frac{3}{2} = -\frac{3}{2}$$
Answer: $$m = -\frac{3}{2}$$ or $$-1.5$$
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2. Find the value of $$\sqrt{\frac{(15.03)^2}{29.21 \times 10.52}}$$
Step 1: Calculate the numerator:
$$(15.03)^2 = 15.03 \times 15.03 = 225.9009$$
Step 2: Calculate the denominator:
$$29.21 \times 10.52 = 307.3492$$
Step 3: Compute the fraction:
$$\frac{225.9009}{307.3492} \approx 0.7353$$
Step 4: Take the square root:
$$\sqrt{0.7353} \approx 0.8576$$
Answer: Approximately $$0.858$$
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3. Solve the system:
$$y = x + 2$$
$$x^2 + y^2 = 28$$
Step 1: Substitute $$y = x + 2$$ into the second equation:
$$x^2 + (x+2)^2 = 28$$
Step 2: Expand:
$$x^2 + (x^2 + 4x + 4) = 28$$
Step 3: Simplify:
$$2x^2 + 4x + 4 = 28$$
Step 4: Subtract 28 from both sides:
$$2x^2 + 4x + 4 - 28 = 0$$
Simplify:
$$2x^2 + 4x - 24 = 0$$
Step 5: Divide entire equation by 2:
$$x^2 + 2x - 12 = 0$$
Step 6: Factor or use quadratic formula.
Factors of -12 that sum to 2 are 4 and -3, so:
$$(x + 4)(x - 3) = 0$$
Step 7: Solve for $$x$$:
$$x = -4 \quad \text{or} \quad x = 3$$
Step 8: Find corresponding $$y$$:
For $$x = -4$$:
$$y = -4 + 2 = -2$$
For $$x = 3$$:
$$y = 3 + 2 = 5$$
Answer: Solutions are $$(x, y) = (-4, -2)$$ and $$(3, 5)$$
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4. Determine value of $$y$$:
$$\sqrt{\frac{y+2}{3-y}} = -15 + 10$$
Step 1: Simplify the right side:
$$-15 + 10 = -5$$
Step 2: Note that the square root function outputs non-negative values. Since right side is negative (-5), equation has no real solution.
Answer: No real solutions.
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5. Find force $$F$$ given:
$$F = G \frac{m_1 m_2}{d^2}$$
$$G = 6.67 \times 10^{-11}$$
$$m_1 = 7.36$$
$$m_2 = 15.5$$
$$d = 22.6$$
Step 1: Calculate $$d^2$$:
$$22.6^2 = 510.76$$
Step 2: Calculate numerator:
$$G \times m_1 \times m_2 = 6.67 \times 10^{-11} \times 7.36 \times 15.5$$
Calculate constant part:
$$7.36 \times 15.5 = 114.08$$
Step 3: Multiply by $$G$$:
$$6.67 \times 10^{-11} \times 114.08 = 7.6067 \times 10^{-9}$$
Step 4: Divide by $$d^2$$:
$$F = \frac{7.6067 \times 10^{-9}}{510.76} = 1.49 \times 10^{-11}$$
Step 5: Round to 3 decimal places in standard form:
$$F = 1.489 \times 10^{-11}$$
Answer: $$F = 1.489 \times 10^{-11}$$ Newtons
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6. Triangle area given:
$$a=3.60, b=4.00, c=5.20$$
Formula:
$$s = \frac{a+b+c}{2}$$
$$A = \sqrt{s(s-a)(s-b)(s-c)}$$
Step 1: Calculate $$s$$:
$$s = \frac{3.60 + 4.00 + 5.20}{2} = \frac{12.80}{2} = 6.40$$
Step 2: Compute each term:
$$s - a = 6.40 - 3.60 = 2.80$$
$$s - b = 6.40 - 4.00 = 2.40$$
$$s - c = 6.40 - 5.20 = 1.20$$
Step 3: Calculate area:
$$A = \sqrt{6.40 \times 2.80 \times 2.40 \times 1.20}$$
Calculate product:
$$6.40 \times 2.80 = 17.92$$
$$17.92 \times 2.40 = 43.008$$
$$43.008 \times 1.20 = 51.6096$$
Step 4: Square root:
$$A = \sqrt{51.6096} \approx 7.186$$
Answer: Area $$\approx 7.186 \text{ cm}^2$$
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7. Find constants $$a$$ and $$b$$ in:
$$F = aL + b$$
Given:
When $$F=5.6$$, $$L=8.0$$
When $$F=4.4$$, $$L=2.0$$
Step 1: Write equations:
$$5.6 = 8a + b$$
$$4.4 = 2a + b$$
Step 2: Subtract second equation from first:
$$(5.6 - 4.4) = (8a - 2a) + (b - b)$$
$$1.2 = 6a$$
Step 3: Solve for $$a$$:
$$a = \frac{1.2}{6} = 0.2$$
Step 4: Substitute $$a$$ into second equation:
$$4.4 = 2(0.2) + b = 0.4 + b$$
Step 5: Solve for $$b$$:
$$b = 4.4 - 0.4 = 4.0$$
Step 6: Find $$F$$ when $$L=6.5$$:
$$F = 0.2 \times 6.5 + 4.0 = 1.3 + 4.0 = 5.3$$
Answer:
$$a = 0.2,$$
$$b = 4.0,$$
$$F = 5.3 \text{ when } L=6.5$$