Point Slope Intercept Form
- Thread starter dzak
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dzak said:
I'm confused, too.
"slope-intercept" form for the equation of a line is
y = mx + b
where "m" is the slope and "b" is the y-intercept, or where the line crosses the y-axis.
"point-slope" form for the equation of a line is
y - y1 = m(x - x1)
where "m" is the slope and (x1, y1) is a point known to be on the line.
"point-slope-intercept" form is not something I'm familiar with.
Perhaps you could check to see if you've typed the problem correctly.
mmm4444bot
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I'm thinking that the posted equation is the given equation in this exercise, and that it needs to be rewritten, but that's a guess.
Slope-Intercept form looks like this:
y = m*x + b
Here's some examples of linear equations in Slope-Intercept form.
y = 4x - 7
y = 550x + 8000
y = (1/2)x + 5/2
y = 0.25x - 1.75
y = -10x - 10
Notice two things. (1) The variable y is all by itself on the lefthand side. (2) There are two terms on the righthand side; the first term is the variable x multiplied by some Real number, and the second term is a Real number not multiplied by x.
That's the Slope-Intercept form. Memorize the pattern.
y = mx + b
The number m multiplying x is the line's slope (a measure of how "quickly" the line rises or falls). The number b is where the line crosses the y-axis.
y = 4x - 7
In this example, y is by itself on the lefthand side. On the righthand side, the first term is the product 4 times x. 4 is the slope. The second term is -7. That's the y-intercept.
In other words, m is 4 and b is -7.
y = (1/2)x + 5/2
By inspecting this example, we can read off a slope of 1/2 and a y-intercept at (0,5/2). See how it works? That is why we call this form the Slope-Intercept form. We can see a line's slope and y-intercept just by looking at the equation.
Now that you know what Slope-Intercept form is, here are the steps that you need to do IF you posted the equation you've been given AND the instructions request you to rewrite it in Slope-Intercept form.
(1) On the righthand side, use the Distributive Property to multiply -3 times (x - 6)
(2) Subtract 3 from both sides of the equation
(3) Combine like-terms on the righthand side
If you need more help, please show what whatever work you can or explain why you're stuck.
Of course, if I've guessed wrongly about what you have and what you've been asked to do with it, you'll need to clarify.
Cheers
Slope-Intercept form looks like this:
y = m*x + b
Here's some examples of linear equations in Slope-Intercept form.
y = 4x - 7
y = 550x + 8000
y = (1/2)x + 5/2
y = 0.25x - 1.75
y = -10x - 10
Notice two things. (1) The variable y is all by itself on the lefthand side. (2) There are two terms on the righthand side; the first term is the variable x multiplied by some Real number, and the second term is a Real number not multiplied by x.
That's the Slope-Intercept form. Memorize the pattern.
y = mx + b
The number m multiplying x is the line's slope (a measure of how "quickly" the line rises or falls). The number b is where the line crosses the y-axis.
y = 4x - 7
In this example, y is by itself on the lefthand side. On the righthand side, the first term is the product 4 times x. 4 is the slope. The second term is -7. That's the y-intercept.
In other words, m is 4 and b is -7.
y = (1/2)x + 5/2
By inspecting this example, we can read off a slope of 1/2 and a y-intercept at (0,5/2). See how it works? That is why we call this form the Slope-Intercept form. We can see a line's slope and y-intercept just by looking at the equation.
Now that you know what Slope-Intercept form is, here are the steps that you need to do IF you posted the equation you've been given AND the instructions request you to rewrite it in Slope-Intercept form.
(1) On the righthand side, use the Distributive Property to multiply -3 times (x - 6)
(2) Subtract 3 from both sides of the equation
(3) Combine like-terms on the righthand side
If you need more help, please show what whatever work you can or explain why you're stuck.
Of course, if I've guessed wrongly about what you have and what you've been asked to do with it, you'll need to clarify.
Cheers