Question

Solve each system by elimination: 3x+2y=-18
5x+6y=-30

Answer 1

ok- remember how in the other one we had to find where we could get a negative and positive value for one of the variables in order to eliminate it? try looking at the x and y values in each equation to see if you can multiply one to get the positive and negative values.

Answer 2

umm i think 12y and 6y? im not sure,correct me if im wrong

Answer 3

???

Answer 4

the 2y and 6y- is that what you meant? (sorry i had to leave my computer)
the 2y can be multiplied by -3 to get -6y, which, when added to 6y, will eliminate it.

Answer 5

OH GOSH! sorry I messed up the problem its suppose to be 3x+12y=-18
5x+6y=-30

Answer 6

ok. haha. yes- then it would be the 12y and the 6y. great job!
do you know what you need to do for the next step?

Answer 7

honestly no.arent you suppose to divide them?...i think

Answer 8

that is how you would find the multiplier (the 3 from the last problem we did)

Answer 9

so then would we have to divide?

Answer 10

12/6 would give us 2, which is what we need to multiply the second equation by to get 12y in that equation. im doing a really poor job of explaining this, i'm sorry.

Answer 11

nah dont worry its ok.im just really thankful that your actually helping me.it helps me better when you draw it though.pictures help me alot better

Answer 12

ok. pictures it is.

Answer 13

3x + 12y = - 18
5x + 6y = - 30 --->(-2)5x + 6y = - 30
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3x + 12y = - 18
-10x - 12y = 60
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-7x = 42
-7x/-7 = 42/-7
x = - 6

now sub -6 in for y in either of the equations.
3x + 12y = - 18
3(-6) + 12y = - 18
- 18 + 12y = - 18
12y = - 18 + 18
y = 0/12 = 0

check...
5x + 6y = - 30
5(-6) + 6(0) = - 30
- 30 + 0 = - 30
- 30 = - 30 (correct)

ANSWER : x = -6 and y = 0

Answer 14

notice how in this one, if you were to add the equations together, neither variable would be eliminated.
thus, we use subtraction to eliminate the variable: