document.write( "Question 1196470: Variables x and y are such that when lg(2y+1) is plotted against x^2, a straight line graph passing through the points (1,1) and (2,5) is obtained.
\n" ); document.write( "a) Find y in terms of x.
\n" ); document.write( "b) find the value of y when x = √3/2.
\n" ); document.write( "c) Find the value of x when y = 2.
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Algebra.Com's Answer #848493 by proyaop(69)\"\" \"About 
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**1. Determine the Equation of the Line**\r
\n" ); document.write( "\n" ); document.write( "* **Given Points:** (1, 1) and (2, 5)
\n" ); document.write( " * Where (x², lg(2y+1)) are the coordinates\r
\n" ); document.write( "\n" ); document.write( "* **Calculate Slope (m):**
\n" ); document.write( " * m = (y2 - y1) / (x2² - x1²)
\n" ); document.write( " * m = (5 - 1) / (2² - 1²) = 4 / 3\r
\n" ); document.write( "\n" ); document.write( "* **Calculate y-intercept (c):**
\n" ); document.write( " * Using point (1, 1):
\n" ); document.write( " * 1 = (4/3) * 1² + c
\n" ); document.write( " * c = 1 - 4/3 = -1/3\r
\n" ); document.write( "\n" ); document.write( "* **Equation of the line:**
\n" ); document.write( " * lg(2y+1) = (4/3)x² - 1/3\r
\n" ); document.write( "\n" ); document.write( "**2. Find y in terms of x (Part a)**\r
\n" ); document.write( "\n" ); document.write( "* lg(2y+1) = (4/3)x² - 1/3
\n" ); document.write( "* 2y+1 = 10^[(4/3)x² - 1/3]
\n" ); document.write( "* 2y = 10^[(4/3)x² - 1/3] - 1
\n" ); document.write( "* y = [10^[(4/3)x² - 1/3] - 1] / 2\r
\n" ); document.write( "\n" ); document.write( "**3. Find the value of y when x = √3/2 (Part b)**\r
\n" ); document.write( "\n" ); document.write( "* y = [10^[(4/3)*(√3/2)² - 1/3] - 1] / 2
\n" ); document.write( "* y = [10^[(4/3)*(3/4) - 1/3] - 1] / 2
\n" ); document.write( "* y = [10^(1 - 1/3) - 1] / 2
\n" ); document.write( "* y = [10^(2/3) - 1] / 2
\n" ); document.write( "* y ≈ 1.8208\r
\n" ); document.write( "\n" ); document.write( "**4. Find the value of x when y = 2 (Part c)**\r
\n" ); document.write( "\n" ); document.write( "* lg(2*2 + 1) = (4/3)x² - 1/3
\n" ); document.write( "* lg(5) = (4/3)x² - 1/3
\n" ); document.write( "* (4/3)x² = lg(5) + 1/3
\n" ); document.write( "* x² = 3/4 * (lg(5) + 1/3)
\n" ); document.write( "* x = ± √[3/4 * (lg(5) + 1/3)]
\n" ); document.write( "* x ≈ ± 0.8799\r
\n" ); document.write( "\n" ); document.write( "**Therefore:**\r
\n" ); document.write( "\n" ); document.write( "* **a) y = [10^[(4/3)x² - 1/3] - 1] / 2**
\n" ); document.write( "* **b) y ≈ 1.8208 when x = √3/2**
\n" ); document.write( "* **c) x ≈ ± 0.8799 when y = 2**
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