59.4k views
5 votes
Find the solution of the system of equations.
-2x - 9y = -3
--7x - 9y = -33

User Camiblanch
by
3.3k points

2 Answers

5 votes

Answer:

x= 6 and y= -1

Explanation:

-2x - 9y = -3

-7x - 9y = -33

I'm going to be solving by elimination. However, you can solve using substitution as well.

So the first step is to eliminate one of the variables. In my opinion, what's easiest is eliminating the y variables. To eliminate you want to variables (that are the same) to equal 0 and cancel out. To do this, all I have to do is subtract. When I subtract I get 0 as shown below. I will also subtract the other variables and numbers in the equations because that's how elimination works.

-2x - 9y = -3

-7x - 9y = -33

5x = 30

-2 - (-7)=5 and -3 - (-33)= 30

There's no solution for the y variable because -9 - (-9)=0, which cancels out so it doesn't have to be written.

after that you get x=6 because you divide by 5 on both sides.

All that's left is to plug in 6 to one of the equations:

-2(6) - 9y= -3

-12 - 9y= -3

+12 +12

-9y= 9

Divide both sides by -9 to get y= -1

User Andrei Cusnir
by
3.5k points
1 vote

Answer:

x = 6 and y = -1

Explanation:

hope this helps

User Costanza
by
3.7k points