First we'll substitute
with 

Then we can separate this.

Then we'll solve this.



Then we'll plug in to find the extraneous solutions (if any)

0.2 x 40
=8
(change the percentage to a decimal)
Hello from MrBillDoesMath!
Answer:
x + 9 and (x + ( i - 7)) are factors
Discussion:
If f(x) has roots -9 and 7-i then
f(x) = g(x)(x - (-9)) (x - (7-i)) ( g(x) is a polynomial of degree less than f(x))
That is, x + 9 and (x + ( i - 7)) are factors of f(x)
BTW: if the coefficients of f(x) are real (not stated in the Question) then the conjugate of 7-i, i.e. 7 + i, is also be a root.
Thank you,
MrB
If A varies directly with z, and A is 30 and z is 5, then when z is 1, A is 6.
z: 5 ÷ 5 = 1
A: 30 ÷ 5 = 6
Then, when z is 1, A is 6
So, when z is 9, A is...
z: 1 × 9 = 9
A: 6 × 9 = 54
A is 54