Given f(x)=-10x2-42x-17

find f(x+h)

Substitute x with x + h.

f(x + h) = -10(x + h)^2 - 42(x + h) - 17

Expand and simplify.

To find f(x+h), we need to substitute (x+h) for x in the equation f(x) = -10x^2 - 42x - 17.

Substitute (x+h) for x:

f(x+h) = -10(x+h)^2 - 42(x+h) - 17

Now we can expand and simplify the equation from here.

Step 1: Expand (x+h)^2
(x+h)^2 = (x+h)(x+h) = x(x+h) + h(x+h) = x^2 + 2xh + h^2

Step 2: Substitute the expanded form into the equation:
f(x+h) = -10(x^2 + 2xh + h^2) - 42(x+h) - 17

Step 3: Distribute the -10 and -42
f(x+h) = -10x^2 - 20xh - 10h^2 - 42x - 42h - 17

And that is the equation for f(x+h).