Question

Solve these systems of equations 7x+2y= -3 and -14x-4y=6 . I got y=3/2,
x= -6/7 am I right ?

Answer 1

hmm multiply first equation with 2

Answer 2

14x+4y=-6

Answer 3

14x+4y+6=0

Answer 4

well yeah i did that multiplying it by -2 so that when i add it in the second question -14x and 14X cancel out (I'm using linear combinations here)

Answer 5

-14x+4y-6=0

Answer 6

*equation

Answer 7

if thats the case both x and y cancels out!!

Answer 8

isnt it?

Answer 9

In the first equation you do 2y times -2 = -4y. Now in the 2nd equation you have -4y soo -4y+ -4y is -8y which means that the ys don't cancel out

Answer 10

nt really :)

Answer 11

infact both these lines are the same !!

Answer 12

take a look at the graph

Answer 13

http://www.wolframalpha.com/input/?i=solve+7x%2B2y%3D+-3++and+-14x-4y%3D6

Answer 14

yes I see...so there's something I'm doing wrong in my math here !

Answer 15

u were right they are the same line!

Answer 16

take a look at the question you have posted !!

Answer 17

:P yep makes sure u type the qns right :)