SOLUTION: im sorry but i need help again on alot this time 1)Write an equation of the line that is parallel to the given line and passes through the given point. y==2x+3, (-4,1) 2)Write

Algebra ->  Equations -> SOLUTION: im sorry but i need help again on alot this time 1)Write an equation of the line that is parallel to the given line and passes through the given point. y==2x+3, (-4,1) 2)Write      Log On


   

Question 876244: im sorry but i need help again on alot this time
1)Write an equation of the line that is parallel to the given line and passes through the given point. y==2x+3, (-4,1)
2)Write an equation in slope-intercept form of the line that passes through the points.(-4,2) (1,-1)
3) Write an equation in slope-intercept form of the line that passes through the points.(-2,-1) (3,5)
4)Write an equation of a line that is perpendicular to y=2x+3 and passes through
(3,4)
tats all for today ... Thank you if you can me again

Found 2 solutions by mananth, richwmiller:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
1 y = 2 x + 3
Divide by 1
y = 2 x + 3
Compare this equation with y=mx+b
slope m = 2
The slope of a line parallel to the above line will be the same
The slope of the required line will be 2
m= 2 ,point ( -4 , 1 )
Find b by plugging the values of m & the point in
y=mx+b
1 = -8 + b
b= 9
m= 2
Plug value of the slope and b in y = mx +b
The required equation is y = 2 x + 9


x1 y1 x2 y2
-4 2 1 -1

The general equation of the line when co-ordinates of two points are given is

%28y-%09y1%29%2F%28%09y1-y2%29+=+%28x-x1%29%2F%28x1-x2%29




%28y%09-2++++++%09%29%2F%28%093++++++%09%29=%28x%09%2B4++++++%09%29+%2F%28%09-5++++++%09%29

+%09-5++++++%09%28y%2B%09-2++++++%09%29+=%093++++++%09%28x-%09-4++++++%09%29

-5 y+ 10 = 3 x+ 12

-5 y= 3 x 2
/ -5
y= - 3/ 5 x+ - 2/ 5
-----------
1 y = 2 x + 3
Divide by 1
y = 2 x + 3
Compare this equation with y=mx+b, m= slope & b= y intercept
slope m = 2

The slope of a line perpendicular to the above line will be the negative reciprocal - 1/2
Because m1*m2 =-1
The slope of the required line will be - 1/2

m= - 1/2 ,point ( 3 , 4 )
Find b by plugging the values of m & the point in
y=mx+b
4 = -3/ 2 + b
b= 11/2
m= - 1/2
The required equation is y = - 1/ 2 x + 11/ 2



m.ananth@hotmail.ca

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
Website rules
a) Limit 5 problems per day
b) No similar problems
c) Submit each problem separately and in only one category.