When simplifying equations that are done simultaneously it is important to make one variable the subject of the formula to simplify solving the equations.
We already have y the subject of the formula of the one equation:
`y = 6x -11`
Now we can make y the subject of the formula for the next equation:
`-3x -2y = 7`
`-3x-7 =2y` (apply inverse operations)
`(-3x-7)/2 = y` (apply inverse operations)
Since we have two equations, we can now equate the two equations and solve for x:
`6x - 11 = (-3x-7)/2`
`2(6x -11) = -3x -7` (inverse operations)
`12x - 22 = -3x -7` (multiply out)
Now get the variable x on the one side, and the constants on the other side:
`12x + 3x = -7+22` (apply inverse operations)
`15x = 15`
`x =1`
Since we know what x is, we can substitute it in the first equation as it is the easiest equation:
`y = 6(1) -11`
`y = -5`
SUMMARY: `x = 1, y =-5`
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