Given that a and 2b are reciprocal to each other, - C and (D / 2) are opposite to each other, / X / = 4, find the value of 4ab-2c + D + (x / 4)

Given that a and 2b are reciprocal to each other, - C and (D / 2) are opposite to each other, / X / = 4, find the value of 4ab-2c + D + (x / 4)

If the distance between the corresponding point of a number on the number axis and the corresponding point of its opposite number on the number axis is half a unit length, then the number is zero______ .
Thank you very much!

The corresponding points of a number and its opposite number on the number axis are symmetric with respect to the origin O. their distances to the origin are equal, which are half of 1 / 2, i.e. 1 / 4. Therefore, the number is 1 / 4 or - 1 / 4

If the distance between the corresponding point of a number on the number axis and its opposite number on the number axis is 0.5 unit length, then the number is zero__ .

You should know the meaning of absolute value!
Draw a number line
Because the distance between the corresponding point of this number on the number axis and its opposite number on the number axis is 0.5
With the definition of absolute value, we can see that these two points are symmetrical about the origin
So the distance between the point and the origin is 0.25
The number satisfying the condition is only plus or minus 0.25

If the point representing the number x on the number axis is to the left of the origin, the result of simplifying | 3x + x2 | is______ ．

The point of ∵ x is on the left side of the origin, ∵ x ＜ 0, ∵ original = | 3x + | x | = | 3x-x | = | 2x | = - 2x. So the answer is - 2x