C, see explanation in the picture attached below.
Unsure of what you're asking.
If you have an algebraic expression in front of you and see a number there, you could label it as "known" or "a known quantity." Another word that comes to mind is "constant."
What are you solving for?
If you are solving for × then I hope this helps
Let's solve for x.
f(x)= 100−10+e−0.1x
Step 1: Add 0.1x to both sides.
xf+0.1x=−0.1x+e+90+0.1x
xf+0.1x = e+90
Step 2: Factor out variable x.
x(f+0.1) = e+90
Step 3: Divide both sides by f+0.1.
x(f+0.1)/ f+0.1 =e+90/ f+0.1
x=e+90/ f+0.1
Answer:
x= e+90/ f+0.1