Which is not a function?
Is the relation y^2+5x=8 a function? Explain.

Question

amistre64 · Answer

in the standard definition; No

amistre64 · Answer

if y axis is up and xaxis is left; this aint a function

anonymous · Answer

The graph of a function can never cut the y-axis in two places. As this contans y to the powewr 2 it implies that the graph will cut in two places the y-axis. Hence not a function.

amistre64 · Answer

it can cut the y axis twice; there is no reason to suggest that y is not the input and x the output; it is only by convention that x is left and right, while y is up and down

anonymous · Answer

Run a vertical line across athe graph of a function and it will only hit the graph in one place at a time, fact.

amistre64 · Answer

thats not a fact, its a convention;  replace x and y with r and t, then what?

anonymous · Answer

Amistre, have you been here all day?

amistre64 · Answer

just got back on actually ;)

anonymous · Answer

I take your point, it is a little pedantic but the conventions of x-axis and y-axis as we both understand them allows my answer to hold.

amistre64 · Answer

it does :)  and it is lol

anonymous · Answer

Which country are you operating from?

amistre64 · Answer

y^2+5x=8

x =  (-y^2 +8)/2  is a function

the other way it is not ....

amistre64 · Answer

usa, florida

amistre64 · Answer

..../5

anonymous · Answer

OK, France and here it is way past the time for bed so bonsoiree my friend

amistre64 · Answer

Ciao ;)