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Question 178979: Find the slope and y-intercept
3x+2y=6 can you explain how y=-3/2 (I keep getting y=3/2) where am I going wrong?
Answer by solver91311(24713) (Show Source):
You can put this solution on YOUR website!
To put an equation into slope-intercept form, solve for y:
Add -3x to both sides:
Multiply by
The slope is now the coefficient on x, namely
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Here's another way to look at it, if perhaps you remain unconvinced:
Start with your original equation.
Select a value for x, anything will do so pick something that will make the arithmetic easy, like 1. Substitute this value into the original equation and calculate the value of y:
So now we know that when , , meaning that one of the points on the line is described by the ordered pair .
Repeat the process with another value of x, say 2.
And we have another point on the line: .
Given two points and , the slope can be calculated using:
Substituting our derived coordinates:
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One more idea to carry around with you in your back pocket. Any time you have a 2-variable linear equation written in standard form where the signs on the two variable terms are the same, you will have a negative slope.
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