Step-by-step explanation:
can you please add details to your question
Ok so assuming that the 'x' means multiply and not 'x' as in placeolder we do
PEMDAS
parenthaseees
exponents
multipilcation or division
additon or subtraction
parethasees simplify first
(8+7)=15
(9-3)=6
now we have
2x(15)-6/2x(6)
multiply
2x15=30
6/2x6=36/2=18
now we have
30-18
12
answer is 12
The roots are 3 and 17 so the distributed equation is
(x-3)(x-17)
distribute
x²-3x-17x+51
x²-20x+51
I hope I've helped!
Answer:
B. 95% confident the average concentration of PCBs in the water supply is between 2.9 ppb and 3.5 ppb
Step-by-step explanation:
You are given the total number of samples, the concentration of lead, and the standard deviation. The standard deviation represents how inaccurate the estimation of the concentration of lead in the drinking water. This means that there can only possibly be a 0.3 ppb error in the estimation. 3.2-0.3=2.9, and 3.2+0.3=3.5