Answer:
A) X + Y = 12
B) 10Y + x = 10x + Y -18
B) 9Y = 9x -18 multiplying A) by -9
A) -9Y = 9x - 72 adding A and B we get
0 = 18x -90
x = 5
The number is 75
Double-Check
7 + 5 = 12
75 -57 = 18
Step-by-step explanation:
Question 1:
For this case, the first thing we must do is define variables.
We have then:
x: number of nickels
y: number of dimes
We write the system of equations that adapts to the problem.
We have then:
0.05x + 0.10y = 6.10
x + y = 67
Solving the system we have:
x = 12
y = 55
Answer:
there are 12 nickels
Question 2:
For this case, the first thing we must do is define variables.
We have then:
x: Allan's score
y: Dave's score
We write the system of equations that adapts to the problem.
We have then:
x + y = 375
x = 2y-60
Solving the system we have:
x = 230
y = 145
Answer:
Dave: 145 Allan: 230
The answer is already given in your question. The inverse of a function
f is f-1, g is g-1, h is h-1 and i is i-1.
To explain why the inverse of
<span>f = {(1,2), (2,3), (3,4), (4,5), (5,6), (6,7)}
is
f-1 = </span><span>f -1 = {(2,1), (3,2), (4,3), (5,4), (6,5), (7,6)}
and that of the other functions to their corresponding inverses is because of the definition of the inverse of a function which is
f = (x, y)
f-1 = (y, x)
Simply, the x and y coordinates of a function are interchanged to get the inverse of the function.</span><span />
Answer:
2. 8x=56
divide both sides of the equation by 8
8x divided by 8=56 divided by 8
any expression divided by itself equals 1
x=56 divided by 8
calculate the quotient
x=7
3. 918 divided by 3= 306
4. answer is 5/21
5&6 not sure
7. inches
8. not sure