Question

Need help please help

Answer 1

I'm assuming it is asking for domain and range and if it is a function or not


ok, so we know this is quadratic, and the form is a function

domain is all real numbers because no value of x will make a restriction like division by 0 or square roots of a negative

range is from the vertex to either positie or negative infinity
find the vertex
ok, so for y=ax^2+bx+c, the x value of the vertex is -b/2a
so
y=1x^2-4x-5
the x value of the vertex is -(-4)/(2*1)=4/2=2
the y value is found by subsituting 2 for x
y=2^2-4(2)-5
y=4-8-5
y=-9
and since the coefinet of the x^2 term is positive, it opens up and the vertex is a min
the range is from y=-9 to inifnity


domain=all real numbers
range is y≥-9
it is a function