N = nickels and q = quarters
0.05n + 0.25q = 1.90
n = 2q + 3
0.05(2q + 3) + 0.25q = 1.90
0.10q + 0.15 + 0.25q = 1.90
0.10q + 0.25q = 1.90 - 0.15
0.35q = 1.75
q = 1.75/0.35
q = 5 ......there are 5 quarters
n = 2q + 3
n = 2(5) + 3
n = 10 + 3
n = 13 <=== there are 13 nickels
Answer:

Step-by-step explanation:
A quadratic equation has one root if the discriminant is 0.
That is we need
for this particular question.
Compare the following to find
:


The variable
is representative of the variable
here.



Plug in into
:


Subtract 4 on both sides:

Divide both sides by 16:

Reduce:

Answer:
C
Step-by-step explanation:
You have to add the whole equation not only a part of it.
3,2,1,6 are all factors of 6.