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In expressions such as "x-y", both "x" and "y" can have any value. The value of "x-y" will depend on what the value of "x" and the value of "y" are.
If you mean: x+y = 30 and the value of y is 15 then the value of x is also 15
The value of x + y is indeterminate. You need the values of both x and y to determine x + y.
y is a function of x iffor each value of x (in the domain) there is a value of y, andfor each value of y (in the range) there is at most one value of x.
if 2x + y = 7, what is the value of y when x = 3?
y = 4x as the value of y changes value of x changes by 4 times :) its simple
In most cases, x is independent and y is dependent. That is, you choose the value of x, but this x-value will decide the corresponding y-value.
If: y = x+b then y-x = b
Y = X - 16 X= Y + 16 X is the original value. Y is the new value of the original value - 16.
y += x means the value y+x is first calculated, and the resulting value is then assigned to y. It is equivalent to y = y+x
It will be 16.
The idea is to replace "x" by its value, to replace "y" by its value, and then to do the calculations.