Answer:
Step-by-step explanation:
9514 1404 393
Answer:
f(x) = -1/2·10^x
Step-by-step explanation:
The y-intercept is -1/2.
The common ratio is (-1/20)/(-1/200) = 10, so the exponential function can be written as ...
f(x) = -1/2·10^x
Answer:
42 1/3
Step-by-step explanation:
We subtract 26 1/6 from 68 1/2. We do this by finding the LCM of 6 and 2. That is 6. We multiply 1/2 by 3/3 to get 3/6. Now, we subtract. 68 - 26 is 42, and 3/6 - 1/6 is 2/6. Our answer is 42 2/6. That can be simplified to 42 1/3.
Answer:
Step-by-step explanation:
5×4+5×3
20+15
25
Answers:
- Total equation: x+y = 80
- Legs equation: 2x+4y = 248
- How many ducks? 36
- How many cows? 44
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Further explanation:
- x = number of ducks
- y = number of cows
x+y = 80 is the total equation (ie the head count equation) since we assume each animal has 1 head, and there are 80 heads total.
That equation can be solved to y = 80-x after subtracting x from both sides.
The legs equation is 2x+4y = 248 because...
- 2x = number of legs from all the ducks only
- 4y = number of legs from all the cows only
- 2x+4y = total number of legs from both types of animals combined
We're told there are 248 legs overall, so that's how we ended up with 2x+4y = 248
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Let's plug y = 80-x into the second equation and solve for x.
2x+4y = 248
2x+4( y ) = 248
2x+4( 80-x ) = 248
2x+320-4x = 248
-2x+320 = 248
-2x = 248-320
-2x = -72
x = -72/(-2)
x = 36
There are 36 ducks
Now use this x value to find y
y = 80-x
y = 80-36
y = 44
There are 44 cows.
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Check:
36 ducks + 44 cows = 80 animals total
36*2 + 44*4 = 72 + 176 = 248 legs total
The answers are confirmed.
