Answer:
5
Step-by-step explanation:
To evaluate (g ○ h)(9), evaluate h(9) , then use this value to evaluate g(x)
h(9) =
= 3, then
g(3) = 2(3) - 1 = 6 - 1 = 5
4x^2 - 30 = 34
4x^2 = 34 + 30
4x^2 = 64
x^2 = 64/4
x^2 = 16
x = sqrt 16
x = -4 and 4......E and F
Given/equations formed from text:
I: l=w+3
II: A=l*w
III: new area B=(l-2)*w
IV: B=A-30
substitute l in II with I to remove l:
II': A=l*w=
(w+3)*w=
w^2+3w
substitute l in III with I to remove l:
III': B=(l-2)*w=
(w+3-2)*w=
(w+1)*w=
w^2+w
substitute A and B from II' and III' into IV:
B=A-30
w^2+w=w^2+3w-30
30=2w
w=15
insert w=15 into I:
l=15+3=18
->
A) dimensions of full size rectangle are width 15 and length 18
dimensions of reduced size rectangle are width 15 and length 16
B) full size: 15*18=10*18+5*18=180+90=270cm^2
reduced size: 15*16=10*16+5*16=160+80=240cm^2
<span>The correct answer is that y does not vary directly with x.
Explanation<span>:
If y varies directly with x, this means that it would fit the equation y=kx for every point in the set.
For the first point, we would have 11=7k; this would mean that k=11//7.
For the second point, we would have 13=8k; this would mean that k=13/8.
Checking using proportions shows us that 11/7 does not equal 13/8:
cross multiply, and you have 11*8=7*13, or 88=91.
This is not true, so k is not a constant, and y does not vary directly with x.</span></span>