Answer:
D, A, B
Step-by-step explanation:
The sign of the leading coefficient always tells you the end behavior on the right: positive = rises; negative = falls.
The degree of the polynomial tells you how the left- and right-end behaviors compare: even = they are the same; odd = they are opposites.
__
A) negative leading coefficient, even degree:
- falls to the left, falls to the right (D)
__
B) positive leading coefficient, odd degree:
- falls to the left, rises to the right (A)
__
C) negative leading coefficient, odd degree
- rises to the left, falls to the right (B)
x = number of 1-cent stamps
y = number of 8-cent stamps
z = number of 12-cent stamps
We have 31 stamps all together, so x+y+z = 31.
"I have 4 more 1-cent stamps than 8-cent stamps" means we have the equation x = y+8. Whatever y is, add 8 to it to get x. Solve for y to get y = x-8.
You also have "twice as many one cent stamps as 12 cent stamps", so x = 2z. Solving for z gets you z = 0.5x
-------------
x+y+z = 31
x+x-8+z = 31 ... y replaced with x-8
x+x-8+0.5x = 31 ... plug in z = 0.5x
2.5x-8 = 31
2.5x = 31+8
2.5x = 39
x = 39/2.5
x = 15.6
Your teacher made a typo somewhere because we should get a positive whole number result for x (since x is a count of how many 1-cent stamps we have).
To do this subtract 2 from each side of the equation to get y = -5, so the value of y in this is -5. Hope this helps!
