SOLUTION: Can anyone help me find the Y-intercept and the X-intercept (the point where the line crosses the X axis) for the line determined by the points (1,-2) and (3,4)? It is not making a

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Question 772649: Can anyone help me find the Y-intercept and the X-intercept (the point where the line crosses the X axis) for the line determined by the points (1,-2) and (3,4)? It is not making any sense to me. What is the formula for this and how do you figure it out? I'm stumped!
Found 2 solutions by stanbon, josgarithmetic:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
find the Y-intercept and the X-intercept (the point where the line crosses the X axis) for the line determined by the points (1,-2) and (3,4)?
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1st: Find the equation of the line:
slope = (4--2)/(3-1) = 6/2 = 3
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Form: y = mx + b
Solve for "b":
4 = 3*3+b
b = -5
Equation:
y = 3x -5
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2nd: Find the intercepts::
x-int:::: ???
Let y = 0, then x = 5/3
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y-int::: ???
Let x = 0, then y = -5
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Cheers,
Stan H.
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Answer by josgarithmetic(39620) (Show Source):
You can put this solution on YOUR website!
(*) Use formula for slope. Compute the slope for the two points.
(*) Use either slope-intercept form for a line OR point-slope form for a line to form the equation for the line.
(*) Rewrite your equation into standard form if you like; but put into slope-intercept form lets you see and read the y-intercept directly.

Formula for slope, , positive three.

To continue with slope-intercept form, y=mx+b,

Substitute either given point to find b.
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OR
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To continue with point-slope form, in which the point (u,v) is one of the points on the line.

Substitute either given point for u and v to continue developing the particular equation.