Question

How do you solve the system of equations `-8x + 12y = 4` and `- 10x - 2y = 22`?

Answer 1

You need to use simultaneous equations.

Explanation:

I prefer substitution but other ways will work. Take one of the equations and solve for either x or y. Then substitute the value for x or y into the second equation.

e.g.
`x-2y=7` and `2x+7y = -8`

`x-2y=7` Solve for x
`x=7+2y` Sub this into equation 2

`2(7+2y)+7y = -8` Solve for y
`14+4y+7y = -8`
`11y=-22`
`y=-2`

From above
`x = 7 +2y` (we now know y = -2)
`x = 7+2(-2)`
`x = 3`