Part (a): We are given two linear equations: 3x + 2y = 3 and 2x – 6y = 1, and we need to find their point of intersection if it exists. The intersection point is the ordered pair (x, y) that satisfies both equations simultaneously. We can solve this system using the elimination method. First, we multiply the first equation by 3 to make the coefficients of y opposites: 3(3x + 2y) = 3(3) gives 9x + 6y = 9. The second equation is 2x – 6y = 1. Now we add the two equations together: (9x + 6y) + (2x – 6y) = 9 + 1, which simplifies to 11x = 10. Therefore, x = 10/11. To find y, we substitute x = 10/11 into the first original equation: 3(10/11) + 2y = 3, which gives 30/11 + 2y = 3. Converting 3 to 33/11, we have 30/11 + 2y = 33/11. Subtracting 30/11 from both sides gives 2y = 3/11, so y = 3/22. Thus the point of intersection is (10/11, 3/22). We can verify by substituting into the second equation: 2(10/11) – 6(3/22) = 20/11 – 18/22 = 20/11 – 9/11 = 11/11 = 1, which confirms our solution.
Part (b): We are told that Celsius (C) and Fahrenheit (F) are related by a linear equation. The slope is given as 5/9, and the C-intercept is given as -100/9. The C-intercept means the value of C when F = 0. In the slope-intercept form of a linear equation, we write C = mF + b, where m is the slope and b is the C-intercept. Substituting the given values, we get C = (5/9)F + (-100/9). Therefore, the linear equation is C = (5/9)F – 100/9. This is the familiar temperature conversion formula rearranged. We can also write it as C = (5F – 100)/9 or multiply both sides by 9 to get 9C = 5F – 100, which is another standard form of the Celsius-Fahrenheit relationship.
Key Takeaways
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The intersection point of two lines is the solution to the system of their equations.
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The elimination method involves making coefficients of one variable opposites and adding equations.
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The slope-intercept form of a line is y = mx + b, where m is slope and b is the y-intercept.
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In the context of temperature conversion, C = (5/9)(F – 32) can be rearranged to C = (5/9)F – 160/9, but here the given intercept differs, indicating a different scaling or possibly a misprint; however, we use the values as provided.