To solve 300=4z-111+3z-12, we first have to combine like terms. As so:
300 = 4z -111 + 3z - 12
300 = 7z - 111 - 12
300 = 7z - 123
Next, we can simplify this even further to get z by itself on one side of the equation:
Let's add 123 to each side:
300 = 7z - 123
300 + 123 = 7z - 123 + 123
423 = 7z
Now, all we have to do is divide 7 to each side, resulting with only z on the right side of the equation:
423 / 7 = 7z / 7
423 / 7 = z
60.42857143 = z (Jeez... long decimal.)
Hope I could help! Have a good one!
If I am wrong, please let me know!