Distribute 4 inside parentheses: First, distribute the 4 inside the parentheses: 4×3a gives 12a, and 4×−x gives −4x. So, we have 3x−[2x+12a−4x].
Combine like terms in brackets: Now, combine like terms inside the brackets: 2x−4x gives −2x. So, we have 3x−[−2x+12a].
Distribute negative sign inside brackets: Next, distribute the negative sign inside the brackets to both terms: −(−2x) gives +2x, and −12a gives −12a. So, we have 3x+2x−12a.
Combine like terms: Finally, combine the like terms 3x and 2x: 3x+2x gives 5x. So, the simplified expression is 5x−12a.
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