Answer:
x=5
Step-by-step explanation:
7x - 4y = 23 and x + y = 8
Multiply the second equation by 4
4x + 4y = 32
Add this to the first equation
7x - 4y = 23
4x + 4y = 32
------------------------
11x = 55
Divide each side by 11
11x/11 = 55/11
x = 5
Answer: d) perpendicular bisectors of
Step-by-step explanation:
Answer:
Approximately $584.43
Step-by-step explanation:
Your formula is A=Pe^rt
A is what you're looking for, the amount
P is the principal aka what you put into the account: $150
e is the mathematical constant. You'd plug that into your calculator.
r is the rate, you'd put it into the equation as a decimal: 8%=.08
t is the time in years: 17
A=150e^.08x17 <em>you can plug this into your calculator</em>
A=$584.43
Answer:
a. closed under addition and multiplication
b. not closed under addition but closed under multiplication.
c. not closed under addition and multiplication
d. closed under addition and multiplication
e. not closed under addition but closed under multiplication
Step-by-step explanation:
a.
Let A be a set of all integers divisible by 5.
Let
∈A such that 
Find 

So,
is divisible by 5.

So,
is divisible by 5.
Therefore, A is closed under addition and multiplication.
b.
Let A = { 2n +1 | n ∈ Z}
Let
∈A such that
where m, n ∈ Z.
Find 

So,
∉ A

So,
∈ A
Therefore, A is not closed under addition but A is closed under multiplication.
c.

Let
but
∉A
Also,
∉A
Therefore, A is not closed under addition and multiplication.
d.
Let A = { 17n: n∈Z}
Let
∈ A such that 
Find x + y and xy


So,
∈ A
Therefore, A is closed under addition and multiplication.
e.
Let A be the set of nonzero real numbers.
Let
∈ A such that 
Find x + y

So,
∈ A
Also, if x and y are two nonzero real numbers then xy is also a non-zero real number.
Therefore, A is not closed under addition but A is closed under multiplication.