Answer: The answer is 8.
Step-by-step explanation: The first step is to convert the expression into figures. We shall call the unknown number Y. So if we are told “the square of a number,” that means Y squared, or better still, Y^2. Further we are told “the difference between the square of a number and 40” and that can be written as;
Y^2 - 40.
Next we are told that this expression is equal to 3 times that number (that is 3Y). That can now be written out as follows,
Y^2 - 40 = 3Y
If we move all expressions to one side of the equation, what we would have is,
Y^2 - 3Y -40 = 0
(Remember that when a positive value crosses to the other side of an equation it becomes negative and vice versa)
We now have a quadratic equation
Y^2 -3Y - 40 = 0
By factorizing we now have
(Y -8) (Y + 5) = 0
Therefore Y - 8 = 0 or
Y + 5 = 0
Hence, Y = 8 or Y = -5
Since we are asked to calculate the positive solution, Y = 8
We could go into calculating the area of the circle using the information we have, but I think this question just wants us to eyeball it.
Does each quadrant of the circle look like it's taking up more than half, or less than half of each square?
Probably looks like more doesn't it.
Which means that there's at least more than 2 square units being taken up by this square.
It also means that it's taking up less than 4 square units, since each square is not being filled up.
Is it more or less than 3?
It's really depends on the perspective on whoever looks at it, but to me personally, it looks like it's more than 3 units long.
Hope this helps.
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Answer:
see explanation
Step-by-step explanation:
Under a reflection in the x- axis
a point (x, y ) → (x, - y ), hence
F(- 1, 9) → F'(- 1, - 9)
G(- 2, 1) → G'(- 2, - 1)
H(- 7, 4) → H'(- 7, - 4)
Answer:
23
Step-by-step explanation:
