what is the x and y intercept for a line passing through the points (-1,5) and (2,-4). I found the slope if that counts, its -3. But I dont know where to go from there, im having a brain fart.
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You found the slope, right? So you know that equation is y = -3x + b.
Plug in one of the two points it passes, like (-1, 5)
5 = (-3)(-1) + b
5 = 3 + b
2 = b
Equation of line: y = -3x + 2
Find your intercepts.
y-intercept: y = -3(0) + 2, y = 2, so (0,2)
x-intercept: (0) = -3x + 2, 3x = 2, x= 2/3. so (2/3, 0)
Plug in one of the two points it passes, like (-1, 5)
5 = (-3)(-1) + b
5 = 3 + b
2 = b
Equation of line: y = -3x + 2
Find your intercepts.
y-intercept: y = -3(0) + 2, y = 2, so (0,2)
x-intercept: (0) = -3x + 2, 3x = 2, x= 2/3. so (2/3, 0)
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Yes the first step was to find the slope! So the equation of your line is now y = -3x + b. Pick either of your points, and plug them into that equation, then you can solve to get b, and have the full equation for your line. Then, make y = 0 in your line equation, and solve for x, which gives you yourr x-intercept. Last, make x = 0 and solve for y, which gives you your y-intercept.
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for the y-intercept, just sub in one of the points as well as the slope into the y=mx+b equation. For the x-intercept, just find the x value when y=0.