13 + 2x = 3
subtract 13 from both sides of the equation
2x = -10
divide by 2 on both sides
x = -5
Answer:

Step-by-step explanation:
Hello,
As the polynomial has only real coefficients, it means that 3-i is a zero too, because we apply the Conjugate Zeros Theorem.
It means that we can write the expression as below, k being a real number that we will have to identify.

And for x = 0, y = -90 so we can write
-90=k*3*10, meaning that k=-3
Hope this helps.
Do not hesitate if you need further explanation.
Thank you
Answer:
The answer is C
Step-by-step explanation:
i also use khan
x=1/2
i hate the minimum word count
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