Answer:
The cost of the diamond last year is x = $ 830
Step-by-step explanation:
Let the cost of diamond last year = x
the cost of diamond present year = y
Given that diamond today cost ten dollars more than twice what it cost last year.
⇒ y = 2 x + 10 ------ (1)
The sum of the cost (last year and this year) is = $ 2500
⇒ x + y = $ 2500 -------- (2)
Put the value of y in equation (2) from equation (1), we get
⇒ 2 x + 10 + x = $ 2500
⇒ 3 x = 2490
⇒ x = $ 830
& y = 2500 - 830
⇒ y = $ 1670
Therefore the cost of the diamond last year is x = $ 830
I do not know what is your question.
Answer:
Step-by-step explanation:
Amplitude is twice the coefficent of the sine function. In this case, 
Period is
divided by the coefficent of x, in this case, 
Phase shift, is how much you sum or subctract from x inside the sine, in this case
.
Midline you get by hiding the sine and reading what's left, in this case, -4.
Answer: 500,000
Step-by-step explanation:
3.5M/7=500,000
Answer:
1 1/3 hours
Step-by-step explanation:
Pipe 1 alone:
fills the pool in 2 hours
in 1 hour, it fills 1/2 of the pool
Pipe 2 alone:
fills the pool in 4 hours
in 1 hour, it fills 1/4 of the pool
Pipe 1 and Pipe 2 working together:
fill the pool in x hours
in 1 hour, they fill 1/x of the pool
Working together, in 1 hour the two pipes fill 1/2 + 1/4 of the pool.
Working together, in 1 hour the two pipes fill 1/x of the pool.
Therefore,
1/2 + 1/4 = 1/x
2/4 + 1/4 = 1/x
3/4 = 1/x
x = 4/3
x = 1 1/3
Answer: 1 1/3 hours