1+1/3a=-6

i get up too 1/3a=-7

That's a good start.

Now, divide both sides of the equation by 1/3.

Remember that when you divide fractions, you must invert the dividing fraction.

then i get -21/1

I should have said, invert the dividing fraction and multiply.

You're right!

-7 / (1/3) = -7 * (3/1)
a = - 21

To solve the equation 1 + (1/3)a = -6, we need to isolate the variable "a". Here's how to do it step by step:

Step 1: Get rid of the constant term on the left side by subtracting 1 from both sides of the equation:
1 + (1/3)a - 1 = -6 - 1
(1/3)a = -7

Step 2: To isolate the variable "a", multiply both sides of the equation by 3:
3 * (1/3)a = -7 * 3
a = -21

Thus, the solution to the equation 1 + (1/3)a = -6 is a = -21.