Answer:
y = -3x +5
Explanation:
In general, do what the question asks you to do: write the equation of the line.
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The slope and y-intercept of the line are given, so the easiest, most direct way to write the equation is to use "slope-intercept form." That form looks like ...
y = mx + b . . . . . . where m is the slope, b is the y-inercept
You are given m = -3 and b = 5, so the equation you are asked to write can be ...
y = -3x +5 . . . . . . this equation is the answer to the question
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Additional comment
There are many forms of the equation for a line. Another one in common use for problems like this is the "point-slope form." You would use that one for a simple, direct answer to writing an equation for a line with a given slope through a given point.
y -k = m(x -h) . . . . . . . line with slope m through point (h, k)
If you are given the x- and y-intercepts, you can use "intercept form" to write the equation:
x/a +y/b = 1 . . . . . for x-intercept 'a' and y-intercept 'b'
Another useful form is "standard form", which has ...
ax +by = c . . . . where a > 0, and a, b, c are mutually prime
For example, the equation for your line could be written in standard form as ...
3x +y = 5