Answer:
20. y = 1/3x +4
21. y -6 = -1/4(x -3)
22. 3x +2y = 8
Step-by-step explanation:
Different forms of the equation of a line can be useful for these different forms of the problem of finding the equation.
20. Given the slope and y-intercept, the slope-intercept form is useful.
y = mx + b
y = 1/3x + 4
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21. Given a slope and a point, the point-slope form of the equation is useful.
y -k = m(x -h) . . . . line with slope m through point (h, k)
y -6 = -1/4(x -3)
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22. Given 2 points, the 2-point form of the equation of a line is useful.
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
y = (4 -(-2))/(0 -4)(x -4) -2
y = -6/4(x -4) -2
y = -3/2x +6 -2
3x +2y = 8 . . . . . . add 3/2x and multiply by 2 (standard form)
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Additional comment
The question asks for "an equation", not "the equation", so we assume that any form is suitable. You may find that your grader will only accept a particular form (usually, point-slope form), so you may have to manipulate these into that form to satisfy your grader.
