Question

Find the zeros of y=x²-1 from a graph.

Answer 1

y = x² - 1

I can find the zeros from a graph, but that won't help you any, because
I'm not about to draw the graph and then post it here.

y = (x + 1) (x - 1)

y = 0 when x = +1 or x = -1.

Answer 2

$y=x^2-1$

$0=x^2-1$

$0=(x+1)(x-1)$

$x+1=0$

$x=-1$

$x-1=0$

$x=1$

$zeros:-1,1$