Consider the problem of finding the line of symmetry and vertex of the quadratic equation f(x) =x^2-8x+15 what is the error in the solution below?
x^2-8x+15=0
x=-8/2 =-8/2=-4 line of symmetry
8^2-8x+15=0
(-4)^2-8(-4)+15=0
16+32+15=0
y=63
(-4,63) vertex
a.
the solution is correct.
b.
the line of symmetry should have been 4 instead of –4.
c.
the vertex is incorrect; it should have been {–4, 53}.
d.
-4^2 should have been squared as –16 instead of 16.