Which of these equations represent functions?

Check all that apply.

A. y = 2x + 1
B. y = x
C. y = root of x-4
D. (x - 1)^2 + (y - 1)^2 = 4

Question

Which of these equations represent functions? 

Check all that apply.

 		A.	y = 2x + 1
 		B.	y = x
 		C.	y = root of x-4
 		D.	(x - 1)^2 + (y - 1)^2 = 4

anonymous · Answer

i know a is a function but what about b,c, and D

ganeshie8 · Answer

b is a line

anonymous · Answer

so a and b are functions

ganeshie8 · Answer

if you have geogebra, plot all of them. and see which one doesnt pass "vertical line" test

ganeshie8 · Answer

yes a and b are functions. we can figure them out directly

ganeshie8 · Answer

c is also obvious if u knw the parabola equation

anonymous · Answer

and D looks like a property

ganeshie8 · Answer

d when you plot you wil see its a circle.

anonymous · Answer

so it's all of them except D!

ganeshie8 · Answer

Yes ! circle intersects the vertical line at two places everywhere... so its not a function