It looks like you might have intended to say the roots are 7 + i and 5 - i, judging by the extra space between 7 and i.
The simplest polynomial with these characteristics would be

but seeing as each of the options appears to be a quartic polynomial, I suspect f(x) is also supposed to have only real coefficients. In that case, we need to pair up any complex root with its conjugate to "complete" f(x). We end up with

which appears to most closely resemble the third option. Upon expanding, we see f(x) does indeed have real coefficients:

Answer:
The number is 5
Step-by-step explanation:
If we need to find the hidden number, Which for simplicity's sake we will denote as "n", lets first write out the equation.
"2 x [n + (-3)] = 4"
We can work through this problem backwards. if we need two times the sum of "n" and (-3) to get to 4, the only number that can be multiplied by 2 to get a product of 4 is 2, so "n" + (-3) must equal 2. so, From here, we can figure out that since 5 + (-3) equals 2, "n" Must equal 5. so, if we plug in 5 for "n" the equation looks like this:
"2 x [5 + (-3)] = 4"
So, since the equation makes sense, the answer is, "n = 5"
5 pounds= 80 ounces
total cost= ($0.44×1)+($0.20×79)=$16.24
Answer:
c. f(x) x+1/x-1
Step-by-step explanation:
To answer this question, we need to check each answer one by one until we find the right one.
y = (x+6)/(x-6)
switch x and y
x = (y+6)/(y-6)
solve for y
x(y-6) = y+6
xy - 6x = y+6
y(x-1) = 6x+6
y = (6x+6) /(x-1) = 6(x+1)/(x-1)
f^-1(x) = 6(x+1)/(x-1)
y = (x+2)/(x-2)
switch x and y
x = (y+2)/(y-2)
solve for y
x(y-2) = y+2
xy -2x = y+2
y(x-1) = 2x+2
y = (2x+2)/(x-1)
f^-1(x) = 2(x+1)/(x-1)
y = (x+1)/(x-1) ------ correct one
switch x and y
x = (y+1)/(y-1)
solve for y
x(y-1) = y+1
xy - x = y+1
y(x-1) = x+1
y = (x+1)/(x-1)
f^-1(x) = (x+1)/(x-1)
f(x) = f^-1(x)