Answer:
11
Step-by-step explanation:
The statement below would be the least effective element of a plan Vitor could use to accurately estimate (or minimize) overdraft fees on the account is he need to <span>use the debit card for a large number of small purchases and check the balance later.</span>
Answer:
a = 3, b = -1, c = 10
Step-by-step explanation:
Let the three numbers be a, b and c.
Equation 1: a + b + c = 12
Equation 2: a + 2b + 3c = 31
Equation 3: 9b + c = 1
Equation 2 - Equation 1:
Equation 4: b + 2c = 19
Equation 3 times by the number 2
Equation 5: 18b + 2c = 2
Equation 5 - Equation 4
17b = -17
b = -1
Substitute into Equation 4:
2c - 1 = 19
2c = 20
c = 10
Substitute into Equation 1:
a + b + c = 12
a - 1 + 10 = 12
a = 3
Given:
The given expression is:
According to Kylie,
To find:
The correct statement for Kylie's explanation.
Solution:
We have,
According to the perfect square trinomial 
.
Kylie did not understand that this is a perfect square trinomial, and she did not determine the product correctly.
Therefore, the correct option is C.
