C. the circumference is the answer
Answer:
D is the correct answer
Step-by-step explanation:
Answer:
24
Step-by-step explanation:
You need to plug in 3 for all of the x-values
That looks like 2(3)^2 + 5(3) - 9
Then if you simplify it is 2(9) + 15 - 9
Then simplify one last time and you get a final answer of 24
The correct expression is (a) n = 100; (x + 10)^2
<h3>How to determine the value of n?</h3>
The expression is given as:
x^2 + 20x + n
Take the coefficient of x
k = 20
Divide by 2
k/2= 10
Square both sides
(k/2)^2 = 100
The above value represents the value of n
i.e.
n = 100
So, we have:
x^2 + 20x + 100
Expand
x^2 + 10x + 10x + 100
Factorize
x(x + 10) + 10(x + 10)
Factor out x + 10
(x + 10)^2
Hence, the correct expression is (a) n = 100; (x + 10)^2
Read more about trinomial at:
brainly.com/question/1538726
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