B) 14.
If you start with subtracting the 8 pages from 50, you get 42 remaining pages. Then it says 2/3 of the REMAINING pages so you divide 42 into thirds. 42/3=14. You want 2/3 of that, so you multiply the 14 by two to get 28 (it's like there are three piles of 14 pages and you want only 2 out of the three piles). So now you've used 28 pages + the original 8. You've used a TOTAL of 36 pages. Subtract 36 from 50 and you get 14 left.
Carry out the mult.: f(x) = -[x^2 - 21x + 9x - 189]
Combine like terms: f(x) = -[x^2 - 12x - 189]
Eliminate the brackets [ ]: f(x) = -x^2 + 12x + 189
Identify coefficients a, b and c: a= -1, b=12, c=189
The equation of the axis of symmetry is x = -b/(2a), which here equals
x = -(12)/[2(-1)], or x = 6
This is also the x-coordinate of the vertex. Plug x=6 into the original equation to calculate the y-coordinate.
Because GH bisects FGI, FGH=HGI
2x+1=3x-9
x=10°
so the measure of HGI is 21°
The linear form of that equation is y=1/4x+2. Your y-intercept should be 2 and the slope is 1/4.