The answer is 12 because you put -3 in the C places which gets you 9 – -3 and then you follow the signs which you would have to add them and get 12
The coefficient of x needs to be 2.
The current coefficient is 2/5.
To eliminate the 5 in the denominator, we can multiply the equation by 5.
We get

Now, to solve the equations, all we need to do is add them.
Hope this helps!
<span>a || b
4x + 72 + 2x - 12 = 180
6x + 60 = 180
6x = 180 -60
6x = 120
x = 120/6
x = 20</span>