Step-by-step explanation:
There is 10 questions which in this case are the trials.
We know we can either get a question right or wrong so the two outcomes are right or wrong.
The probability that a student choose the right outcome is 1/4. since there is one right answer out of 4 chocies.choices.
Yes, the trials likelihood outcome of each outcome is the same. so it's independent
Answer:
I have attached the work to your problem.
Please see the attachment below.
I hope this helps.
Answer:
x = ± - 3
Explanation:
I'm assuming you want the solutions to that equation, so here goes! (If not, please comment.)
(x-3)(x+9)=27
Let's FOIL this all out and expand. (Remember: First, Outer, Inner, Last.)
x^2 + 9x - 3x - 27
(first+ inner + outer + last)
x^2 + 9x - 3x - 27 = 27
Combine like terms, and add 27 to both sides.
x^2 + 6x - 27 + 27 = 27 + 27
x^2 + 6x = 54
Let's complete the square, because factoring doesn't work, and because it's good practice.
x^2 + 6x + ___ = 54 + ____
In the blank we will put b/2 ^2 = 6/2 ^2 = 3^2 = 9 to complete the square.
x^2 + 6x + 9 = 54 + 9
Now we've got a perfect square factor:
(x + 3)^2 = 63
sqrt(x+3)^2 =
x + 3 = ±
x = ± - 3
2/36 or 5.55...%(repeated 5).