Answer:
Krista put 0.40 in the first equation meant for the number of stamps.
Step-by-step explanation:
Krista's equation
0.40x+y=45
x+0.55y=18.75
The system of Equation should have been
x + y = 45 (1)
0.40x + 0.55y = 18.75 (2)
From (1)
x=45-y
Substitute x=45-y into (2)
0.40(45 - y) + 0.55y = 18.75
18 - 0.40y + 0.55y = 18.75
Collect like terms and you now have
0.55y - 0.40y = 18.75 - 18
0.15y = 0.75
Divide both sides of the equation by 0.15
y = 5
Substitute y=5 into (1)
x + y = 45
x+5=45
x=45-5
x=40
This shows that the stamps that cost 0.40 cents were 40 while those that cost 0.55 cents were 5 in number.
Krista's error:
Krista put 0.40 in the first equation meant for the number of stamps.
Answer: Overall, the steps for algebraically finding the range of a function are:
Write down y=f(x) and then solve the equation for x, giving something of the form x=g(y).
Find the domain of g(y), and this will be the range of f(x). ...
If you can't seem to solve for x, then try graphing the function to find the range.
Step-by-step explanation:
Answer:
28
Step-by-step explanation:
- 28 is a multiple of 7, multiply it by 2 is 56 and it is greater than 22.
if you find another answer too, let me know
first term: 5x-5y
common difference: -x/2 + y