1. 4y2 = 36 - 9x2
2. y = x2 - 3x - 4
3. x2 + y2 = 4
4. x = y2 - 6x + 8
2007-04-09 07:54:04 · 5 answers · asked by Greg L 3 in Science & Mathematics ➔ Mathematics
Assuming x2 = x squared, #2 is a function (parabola): one value of y for any value of x. #1 and #3 are circles, and I'm not sure what #4 is (doesn't really matter)
2007-04-09 07:58:33 · answer #1 · answered by chiyaniwatori 2 · 0⤊ 0⤋
What makes some thing a function? In a function, the enter "x" can't map to better than one "y" The equation y^2 = x isn't a function as a results of fact if x is 4, y may be -2 and a couple of. In our equation, we are in a position to unravel for y and notice that one x maps to purely one y. as a result, that's a function.
2016-10-21 10:59:16 · answer #2 · answered by ? 4 · 0⤊ 0⤋
Equations 1 and 3 are circles and cannot be functions since on value of x can have two values of y.
Equation 2 is a parabola with axis of symmetry parallel to the y-axis. Therefore there is one uniqe value for eac value oxf x and therefore it is a function.
Equation 4 is a parabola with axis of symmetry parallel to the x-axis and therefore will give two different values of y for each value of x and cnnot be a function.
2007-04-09 08:12:00 · answer #3 · answered by ironduke8159 7 · 0⤊ 0⤋
2. y = x2 - 3x - 4 only
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Reason:
For each x value, you have exactly one y value.
2007-04-09 07:58:57 · answer #4 · answered by sahsjing 7 · 0⤊ 0⤋
2 .. (see vertical line test)
1) ellipse
2) parabola wrt Y(OK) (with respect to)
3) circle
4) parabola wrt X (no good)
2007-04-09 07:59:24 · answer #5 · answered by Brian D 5 · 0⤊ 0⤋