Question

3x-9y =81
2x-6y=-10 solve then classify the system

Answer 1

did you try elimination method or addition method

Answer 2

ive been working with the elimination method i wonder if the substitution method might work too but i havent gotten the right answer either way

Answer 3

either way will work
for this problem i think elimination is easier

lets cancel out the x's
LCM of 2 and 3 is 6
multiply 1st row by -2
multiply 2nd row by 3

-6x +18y = -162
6x -18y = -30
______________________
0 + 0 = -192
0 = -192
this is False
No solution

Answer 4

system is inconsistent

Answer 5

if this occurs, then it's Undefined...

Answer 6

that means it would be dependent as well right?

Answer 7

x=dependent
y=independent
and since u don't know either one. "Undefined"
then it can't be dependent or independent. unless i'm not seeing something here.

Answer 8

what do you mean undefined??
no not dependent, thats only if there are infinite solutions
no solution means these 2 lines are parallel, same slope

Answer 9

Oh. True sorry i wasn't looking at it like this. Just haven't done this for a long time...

Answer 10

ok so it would be independent and inconsistent since both are parallel

Answer 11

correct

Answer 12

ok now the last part of the question to this one is to show it in graph form what would this problem look like graphed

Answer 13

where do you think you were messing up?

Answer 14

graph both lines
either by putting them in y=mx+b form
or
make a table of x,y values and connect the points

Answer 15

whats bad is im trying to learn algebra in a 9 week period and ive never done it in my life back in high school we had the whole yr to learn this

Answer 16

oh online class ? yeah that can be hard

Answer 17

it is very frustrating

Answer 18

so y=(81-3x)/-9 and y=(-10-2x)/-6

Answer 19

I've taken online math before. But it's always gave me an option to view and example of the problem how to solve. It's harder for u...

Answer 20

im posting problems i have trouble with and am hoping to see them worked out with the answer so i can see how they are done but many just give me the answer which is not helping

Answer 21

the graphing problems are hardest becaise noone really can show me what they look like

Answer 22

have you herd of Graphing Calculators?
Texas Instruments...

Answer 23

@beehive
yeah those examples can be really helpful but they dont answer everyones questions and you dont know why you do the steps it shows you to do

Answer 24

graphcalc.com
free graphing software

Answer 25

ill chk it out im gonna post a few more and head to bed my head istarting to hurt lol