This is 4x=2x-2 as a graph
10% of what is 9...
0.10x = 9
x = 9/0.10
x = 90.....he has 90 all together
12x^2+62x+80
Do you want a step by step?
T = 4. first, you can add 2 to both sides of the equation. you get 4t = 16. then, you can divide both sides by 4 to isolate t.
I believe it is 20 and 15