Math help? **10pts?

Question

write and equation of the line that passes through each pair of points

answer and explain prob.

1) (3,-2), (6,4)

2) (2,-2), (3,2)

Answer 1

1.) first get the slope...

m=(y-y1)/(x-x1)
m=(-2-4)/(3-6)
m=-6/-3
m=2

then find the y-intercept...

y=mx + b

choose a point (x & y) from any of the points in the given problem, then substitute....

for instance: (3,-2)

-2= 2(3) + b
-2-6=b
b=-8

so the equation would be:

y= 2x-8 or 2x-y-8=0

2.) Same process for no.2...

m=(-2-2)/(2-3)
m=0

y=mx + b
-2=0(2) + b
b=-2

y=-2 would be the equation...



piece of cake!!!

Answer 2

First you need to find the slope by finding the rise over the run:

(-2 - 4)/(3-6)

Then plug the slope into the eqn:

y = mx + b

where m is the slope.

Then plug in a point that's been given and solve for b. Take these parts (m and b) and piece them together to get the eqn.

You do the same thing for the second pair.

Answer 3

What I like to do is think about a point on the line going through the given points. Since the slope of a line is always constant:

Equate the slope of an arbitrary (x,y) on the line to the slope between the given points:

(y-(-2))/(x-3) = (4-(-2))/(6-3) , now grind it out and you'll have the equation of the line.

Answer 4

find the slope:
Y2-Y1/X2-X1 (rise/run) 4-(-2)/(6-3) = 6/3= 2

then use the point slope form:
Y-Y1=M(X-X1) plug in and get Y-(-2)=2(X-3)= Y+2=2X-6
M= slope -2 -2
Y=2X-8 is the equation
same for #2

Answer 5

1) slope=4+2 over 6-3 =6/3=2
use
y-y1=m(x-x1
y-4=2(x-6)

or
y=2x-8

2)
slope=4/1=4
y-2=4(x-3)
or
y=4x-10

Answer 6

use the following equation:

1) (y-y1)/(x-x1)=(y2-y1)/(x2-x1)

with x1=3, y1= -2, x2=6 and y2=4

(y- -2)/(x-3)=(4- -2)/(6-3)
(y+2)/(x-3)=(4+2)/3
(y+2)/(x-3)=6/3
(y+2)/(x-3)=2
2x-6=y+2
2x-y=8

2) (y-y1)/(x-x1)=(y2-y1)/(x2-x1)

with x1=2, y1= -2, x2=3 and y2=2

(y- -2)/(x-2)=(2- -2)/(3-2)
(y+2)/(x-2)=(2+2)/1
(y+2)/(x-2)=4
4x-8=y+2
4x-y=10

Answer 7

consider the equation

y=mx+c

those points satisfies the eq'n

hence get the value of m,c.

Answer 8

if we have two pts (x1,y1) & (x2,y2)
then eqn of line is :
y - y1=m(x-x1)
m=(y2-y1)/(x2-x1)

1) y+2=2(x-3)
2) y+2=4(x-2)
thanks
& goodluck