Question

3x - 5y = -9
8x - y = 13
Choose one answer.
a. (-2,3)
b. (3,-2)
c. (3,2)
d. (2,3)

Answer 1

See, here multiply second equation with 5 both the sides, what you got??

Answer 2

i dnt understand

Answer 3

See, in first equation, what is the coefficient of y??

Answer 4

5

Answer 5

Is it??

Answer 6

I think -5...

Answer 7

ohhhh yes -5

Answer 8

And in second equation??

Answer 9

-1

Answer 10

rite?

Answer 11

Firstly make both the y coefficients equal..
How can you do that??

Answer 12

Yes you are right...

Answer 13

uhmm idk

Answer 14

See, y coefficient is -1..
What number I should multiply with -1 to get -5???

Answer 15

5

Answer 16

Yes, that is why I am multiply second equation with 5..
Getting??

Answer 17

yes!

Answer 18

So, multiply both sides of second equation by 5 what will you get??

Answer 19

idk if this is rite but 8x-5y=65?

Answer 20

You are close..
See, what I am saying is :

5(8x - y = 13)

You did not multiply 5 with 8x that is the mistake..

Answer 21

ohk so im distributing its 40x-5y=65

Answer 22

Yes now you are right..

So, what are the two equations now become/

I am writing both the equations:

3x - 5y = -9 ------------1
40x - 5y = 65 ------------2

Now simply subtract them and tell what will you get??

Answer 23

then i get -37x=-74
x=2?

Answer 24

Yes you did that very right..
Can you find y now??

Answer 25

y=1?

Answer 26

Now solve it again..

Answer 27

ohk

Answer 28

y=3

Answer 29

See, 3x - 5y = -9

Or, 3(2) - 5y = -9
6 - 5y = -9

-5y = -9 - 6

5y = 15

And get y from here..

Answer 30

Yes, you are right then what is the answer then??

Answer 31

d!

Answer 32

That is correct...

Answer 33

thanks again!!