If i understood the question right, you're trying to find the value when h = -2. If that's true so here is how it's done:

Answer:
We can call the amounts of red, gray, and brown dye 1 1/8x, 3/4x and 5/8 x respectively and we can write the equation:
1 1/8x + 3/4x + 5/8x = 20
2 1/2x = 20
x = 8 which means that the stylist needs 1 1/8 * 8 = 9 oz red, 3/4 * 8 = 6 oz gray and 5/8 * 8 = 5 oz brown.
8. complementary angles = 90°
3x+3+10x-4 = 90
13x-1 = 90
13x = 91
so x = 91/13= 7
then K = 3(7)+3 = 24°
so L = 10(7)-4 = 70-4 = 66°
9. P is three less than twice of Q
so P = 2Q-3
supplementary angles = 180°
P+Q = 180
(2Q-3)+Q = 180
3Q-3 = 180
3Q = 183
so Q = 183/3 = 61°
then P= 2(61)-3 = 122-3 = 119°
10. B is two more than three times of C so B= 3C+2
complementary angles = 90°
B+C= 90
(3C+2)+C=90
4C+2=90
4C= 88
so C= 22°
then B = 3(22)+2= 66+2 = 68°
Answer:
6
Step-by-step explanation:

Simple problem:
When simplifying 3(x-6) they subtracted 3 instead of multiplied by 3.
3(x-6) should be 3x-18.
Now when you simplify:
3x-18+4x+12-6x
Which is x -6 =0
Or x =6