Simplify 12-[-3+(6t-9)]

Work from the inside out:

                                                        12 - [ -3 + (6t - 9) ]

REmove the inner parentheses:  =  12 - [ -3 + 6t - 9 ]

Combine -3 and -9:                    =  12 - [ 6t - 12 ]

Distribute the negative sign:      =  12 - 6t + 12

Combine 12 and 12:                   =  24 - 6t

It equals 18 if you take out the t (I'm assuming it's a typo)

No, t is supposed to be there and is a variable

Thank you!

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