Answer: Choice B
(-2, 5)
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Explanation:
The original system is
Multiply both sides of the second equation by 3. Doing so leads to this updated system of equations
Now add straight down
The x terms add to -4x+3x = -1x = -x
The y terms add to 3y+(-3y) = 0y = 0
The terms on the right hand sides add to 23+(-21) = 2
We end up with the equation -x = 2 which solves to x = -2
Now use this to find y. You can pick any equation with x,y in it
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-4x+3y = 23
-4(-2)+3y = 23
8+3y = 23
3y = 23-8
3y = 15
y = 15/3
y = 5
Or
x-y = -7
-2-y = -7
-y = -7+2
y = -5
y = 5
Either way, we get the same y value.
So that's why the solution is (x,y) = (-2, 5)
Answer:
i am pretty sure it's B correct me if i am wrong
Step-by-step explanation:
Answer:
<u>Option D: A cylinder with a circumference of about 50 units</u>
Step-by-step explanation:
The rest of the question is the attached figure.
The square shown has a perimeter of 32 units. The square is rotated about line k. What shape is created by the rotation and what is the approximate circumference of the base? Circumference of a circle: C = 2πr
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Given: the perimeter of the square = 32
perimeter of a square is four times the length of its side
So, the side length of square = 32/4 = 8 units
The square is rotated about line k.
So, it will form a cylinder with radius 8 units.
Circumference of a circle = 2 π r
Where, r is the radius of the circle.
Circumference of the base is C = 2 π * 8
∴ C = 16π = 16 * 3.14
∴ C = 50.26548 ≈ 50
The shape is created by the rotation is a cylinder with a circumference of about 50 units.
<u>So, the answer option is D.</u>
Answer:
87
Step-by-step explanation:
Smaller number = 43
Bigger number= 44
Sum = 43+44
