I am not sure about this but here goes nothing: d=2.5t+2.2 is very familiar to y=mx+b y=d m=2.5 x=t b=2.2 to find a new quasion we substitute d and t into place wich equals 1=2.5(0)+b simplification and you get b=1 so your answer is d=2.5t+1
There are a couple of ways you can solve this. You can write it out like
(K-3)(K-3)(K-3)(K-3)(K-3)(K-3)(K-3)
And pretty much use the foil method
Or you can use the binomial theorem (google it if you dont know)
The solution should be:
(K^7) - 21(k^6) + 189(k^5) - 945(k^4) + 2835(k^3) - 5103(k^2) + 5103k - 2187
Answer: This is what Khan Academy said the answer was
By plugging (k-2) in t, we can write that
