Write an explicit formula, term of sequence HELP I DON’T UNDERSTAND here’s a picture: and all my points

= 10n - 5

Step-by-step explanation:

There is a common difference d between consecutive terms, that is

d = 15 - 5 = 25 - 15 = 10

This indicates the sequence is arithmetic with n th term

= a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = 5 and d = 10 , then

= 5 + 10(n - 1) = 5 + 10n - 10 = 10n - 5

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4