Each question has four choices, then the probability to guess a correct answer is

and the probability to select incorrect choice is

.
You have a 5-question multiple-choice test, then n=5. The <span>probability that you will guess exactly three out of five questions correctly is </span>
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</span><span>

</span>

.
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Answer:
x = - 3 ± 
Step-by-step explanation:
x² + 6x + 7 = 0 ( subtract 7 from both sides )
x² + 6x = - 7
using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(3)x + 9 = - 7 + 9
(x + 3)² = 2 ( take square root of both sides )
x + 3 = ±
( subtract 3 from both sides )
x = - 3 ± 
Answer:
B
Step-by-step explanation:
You have to evaluate the power and calculate the sum or difference in order to get the answer
Answer: = x11+x2+2
Step-by-step explanation:
Too hard for me. I'm only in 5th grade