Question
Use the point-slope form linear equation given to complete the following problems.
y-3=3(x+1)
1. What is the slope of the given line?
Here's what I did:
y-3=3(x+1)
y-3+3=3x+3
y=3x+6
m=3
Correct so far?
2. What point does this line pass through, which is the basis of this equation?
I said (0,6)
3.Rewrite this equation in slope-intercept form.
I did this:
y=3x+6
4, What is the y-intercept of this line?
I said:
b=6
5. Rewrite the equation in standard form.
What I did:
Ax+By=C
3x=y=6
Is this correct?
6. What is the x-intercept of this line?
I'm not sure about this.
If you could check my work and help me complete the problems, I'd be so grateful.
y-3=3(x+1)
1. What is the slope of the given line?
Here's what I did:
y-3=3(x+1)
y-3+3=3x+3
y=3x+6
m=3
Correct so far?
2. What point does this line pass through, which is the basis of this equation?
I said (0,6)
3.Rewrite this equation in slope-intercept form.
I did this:
y=3x+6
4, What is the y-intercept of this line?
I said:
b=6
5. Rewrite the equation in standard form.
What I did:
Ax+By=C
3x=y=6
Is this correct?
6. What is the x-intercept of this line?
I'm not sure about this.
If you could check my work and help me complete the problems, I'd be so grateful.
Answers
Reiny
You did well.
Some small errors
from y-3 = 3(x+1)
y-3 = 3x + 3
at this point you did:
y-3+3 = 3x+3
should have been
y-3+3 = 3x+3 + 3,
then
y = 3x + 6, which you have (so there were actually two errors here)
#2, looking at y-3 = 3(x+1)
and comparing it to the point-slope form of
y - y1 = m(x - x1)
our point was (-1,3)
#3, #4 are good
#5 should be:
3x - y = -6
If your equation is in standard form, the x-intercepts can be done in your head.
for the x-intercept, let y = 0
put your little pinkie finger over the y term (it is zero), then 3x = -6 ----> in your head, x = -2
for the y-intercept, let x=0
put your pinkie finger over the x term,
---> -y = -6 or y = 6 , which is also the b in y = 3x + 6
Some small errors
from y-3 = 3(x+1)
y-3 = 3x + 3
at this point you did:
y-3+3 = 3x+3
should have been
y-3+3 = 3x+3 + 3,
then
y = 3x + 6, which you have (so there were actually two errors here)
#2, looking at y-3 = 3(x+1)
and comparing it to the point-slope form of
y - y1 = m(x - x1)
our point was (-1,3)
#3, #4 are good
#5 should be:
3x - y = -6
If your equation is in standard form, the x-intercepts can be done in your head.
for the x-intercept, let y = 0
put your little pinkie finger over the y term (it is zero), then 3x = -6 ----> in your head, x = -2
for the y-intercept, let x=0
put your pinkie finger over the x term,
---> -y = -6 or y = 6 , which is also the b in y = 3x + 6