Final answer:
To find equations of lines parallel or perpendicular to a given line, use the same slope for a parallel line and the negative reciprocal of the slope for a perpendicular line. Apply the point that the line must pass through to determine the specific y-intercept for each case.
Step-by-step explanation:
To solve this problem, one must understand the concept of the slope and y-intercept of a linear equation. Given the equation of a line in slope-intercept form, y = a + bx, we know that 'b' represents the slope, and 'a' represents the y-intercept. When finding a line parallel to a given line, the slope must be the same, while the y-intercept may differ. To find a perpendicular line, one must use the negative reciprocal of the given line's slope.
For example, if we are given a line with the equation y = 2 + 3x and we want a line that is parallel through point (1, 4), the new line will have the same slope, 3, so its equation will start with y = 3x + c. Substituting the point (1, 4) into this equation gives us 4 = 3(1) + c, which after solving gives c = 1. So the equation of the parallel line is y = 3x + 1.
To find a perpendicular line through the same point (1, 4), we use the negative reciprocal of 3, which is -1/3. The equation starts as y = -1/3x + d. Substituting the point (1, 4) into this equation gives us 4 = -1/3(1) + d, which after solving gives d = 13/3. So, the perpendicular line's equation is y = -1/3x + 13/3.