Answer:
I think your question is not complete..
can you write the question in a way which will determine in what way you want your answer..
i mean from what to find x..
Area is given as 285cm
what is 15 cm for?
from here where is x given to find?
Answer:
Factored form is 4x(2x+3)
Step-by-step explanation:

The factors are
8x^2 ----> 2*2*2*x*x
12x -------> 2*2*3*x
GCF is 2 * 2 * x= 4x
Now we factor out GCF from 8x^2 + 12x
When we factor out GCF, divide each term by 4x

4x(2x +3)
Factored form is 4x(2x+3)
Answer:
Step-by-step explanation:
Let X be the SRS scores of students.
Given that X is normal with standard deviation about 6.5.
Mean difference =
is desired
i.e. Z score should be 
Std error = std deviation of sample = 0.447
b) 
So std error must be 0.997 and sample size must be atleast 193 to get the difference of x bar and mu to lie within 1.3 points in either direction
0.43 is the answer to your question