The solution to the system of equations are (2, 5).
Solution:
The system of equations are
x + y = 7 – – – – (1)
2x – y = –1 – – – – (2)
To find x from equation (1):
x + y = 7
Subtract y from both sides of the equation, we get
⇒ x + y – y = 7 – y
⇒ x = 7 – y – – – (3)
Substitute (3) in (2) we get,
2(7 – y) – y = –1
14 – 2y – y = –1
14 – 3y = –1
Subtract 14 from both sides,
–3y = –15
Divide by –5 on both sides,
y = 5
Substitute y = 5 in equation (3)
x = 7 – 5
x = 2
The solution to the system of equations are (2, 5).
Answer:
see below
Step-by-step explanation:

Answer: 10/ 147
Step-by-step explanation:
Answer:
S= 36.76
Step-by-step explanation:
S = area of base +(base of perimeter*Slant height)*1/2
S = 4*4+((4+4+4)/2)*3.46
S = 16+((12/2)*3.46)
S = 16+6*3.46
S = 16 + 20.76
S = 36.76 cm^2
Answer:
a) The estimated standard deviation of the sampling distribution of the proportion is 0.023
b) the estimated standard deviation have been if he had surveyed only 100 customers is 0.046
Step-by-step explanation:
given information:
the number of sample, n = 400
sample proportion, p = 70% = 0.7
a) standard deviation of a sample proportion is
σ = 
= 
= 0.023
b) if n = 100, so
σ = 
= 
= 0.046