Answer:
x = (13) ^ 1/3
x is approximately 2.351334688
Step-by-step explanation:
x^3 + 7 = 20
Subtract 7 from each side
x^3 + 7-7 = 20-7
x^3 = 13
Take the cube root of each side
x^3 ^ 1/3 = (13) ^ 1/3
x = (13) ^ 1/3
x is approximately 2.351334688
Answer: the graph farthest to the right is almost correct. If you substitute values for x in the function f(x)= -3√x , the output does not match the curve on the graphs shown.
If you have a choice that includes only a curve to the right of the y- axis, that would be better.
Step-by-step explanation: Square roots of Negative x-values will result in imaginary numbers. Otherwise the graph with the curve passing through coordinates (1,-3) (4,-6) and (9,-9) is a good choice.
(And ask your teacher about the square root of negative numbers on this graph.)
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.
You didn't show all answer choices unfortunately, but basically during neap tide, the moon is either above or below the earth, in pictures (vertical). And the right half will always be in shadow.
~Hope this helps
