-12-9(t-3) = 78
Multiply -9 by t and -3 so:
-9(t-3)
-9t + 27
Now add that back to the equation:
-12 -9t +27 = 78
Now combine -12 and 27:
-12-9t +27 =78
15 -9t = 78
Since 15 is positive ( there is no - sign), we need to subtract 78 by 15:
15 -9t = 78
-15 -15
We subtracted and not added because the opposite of addition is subtraction. Now, we have:
-9t = 63
To find t, we need to divide -9t because we are trying to get t to be alone, so:
-9t = 63
————-
-9t -9t
So now, we have:
t= -7
We have a positive t because a negative divided by a negative is equal to a positive.
So, the answer is :
t = -7
Hope this helps, and would you please rank this brainiest?
