7(u-3)+2u=-30
expand the parenthesis to
7u-21 + 2u=-30
combine the u's, add 21 to each side.
To expand the parentheses, you need to distribute the coefficient of 7 to both terms inside the parentheses. That means you multiply both 7 and (u-3) by 7:
7(u-3) = 7u - 21
Now that we have expanded the parentheses, the equation becomes:
7u - 21 + 2u = -30
Next, you have to combine the like terms. In this case, the like terms are the terms with 'u'. Add 7u and 2u together:
7u + 2u = 9u
Now, the equation becomes:
9u - 21 = -30
To isolate the term with 'u', you need to get rid of the constant term -21 on the left side. To do this, you add 21 to both sides of the equation:
9u - 21 + 21 = -30 + 21
Simplifying, you get:
9u = -9
Finally, to solve for 'u', divide both sides of the equation by 9:
(9u)/9 = -9/9
This simplifies to:
u = -1
So, the solution to the equation is u = -1.