Question

4.)
5x+4y=-30
3x –9y=-18
What is the solution to this problem

Answer 1

`5x + 4y = - 30 | * ( - 3) \\ 3x - 9y = - 18 | * 5 \\ \\ - 15x - 12y = 90 \\ 15x - 45y = - 90`

Now add 2 equations

`- 57y = 0 \\ y = 0`

Now we need to put y into any equation

`- 15x - 12 * 0 = 90 \\ - 15x = 90 \\ x = - 6`

Answer: (-6;0)