changing the z to an x makes things easier to visualize for me...

-12 = -3 / 5x multiply both sides by -1/3 (-12 * -1/3 = 4) and (-3/5x * -1/3 = 1/5x)

this step is kinda optional i guess... it just simplifies the problem so you work with smaller numbers.

4 = 1 / 5x or same thing as 4 = (1/5)x

now divide both sides by (1/5)

4/(1/5) = xd

dividing by a fraction is the same as multiplying by its reciprocal

4*5 = x

so yeah... its actually x = 20. or i guess z = 20.

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