![\bf n^{th}\textit{ term of an arithmetic sequence} \\\\ a_n=a_1+(n-1)d\qquad \begin{cases} n=n^{th}\ term\\ a_1=\textit{first term's value}\\ d=\textit{common difference} \end{cases} \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ a_n=2-5(n-1)\implies a_n=\stackrel{\stackrel{a_1}{\downarrow }}{2}+(n-1)(\stackrel{\stackrel{d}{\downarrow }}{-5})](https://tex.z-dn.net/?f=%5Cbf%20n%5E%7Bth%7D%5Ctextit%7B%20term%20of%20an%20arithmetic%20sequence%7D%20%5C%5C%5C%5C%20a_n%3Da_1%2B%28n-1%29d%5Cqquad%20%5Cbegin%7Bcases%7D%20n%3Dn%5E%7Bth%7D%5C%20term%5C%5C%20a_1%3D%5Ctextit%7Bfirst%20term%27s%20value%7D%5C%5C%20d%3D%5Ctextit%7Bcommon%20difference%7D%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20%5Crule%7B34em%7D%7B0.25pt%7D%5C%5C%5C%5C%20a_n%3D2-5%28n-1%29%5Cimplies%20a_n%3D%5Cstackrel%7B%5Cstackrel%7Ba_1%7D%7B%5Cdownarrow%20%7D%7D%7B2%7D%2B%28n-1%29%28%5Cstackrel%7B%5Cstackrel%7Bd%7D%7B%5Cdownarrow%20%7D%7D%7B-5%7D%29)
so, we know the first term is 2, whilst the common difference is -5, therefore, that means, to get the next term, we subtract 5, or we "add -5" to the current term.

just a quick note on notation:
![\bf \stackrel{\stackrel{\textit{current term}}{\downarrow }}{a_n}\qquad \qquad \stackrel{\stackrel{\textit{the term before it}}{\downarrow }}{a_{n-1}} \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{current term}}{a_5}\qquad \quad \stackrel{\textit{term before it}}{a_{5-1}\implies a_4}~\hspace{5em}\stackrel{\textit{current term}}{a_{12}}\qquad \quad \stackrel{\textit{term before it}}{a_{12-1}\implies a_{11}}](https://tex.z-dn.net/?f=%5Cbf%20%5Cstackrel%7B%5Cstackrel%7B%5Ctextit%7Bcurrent%20term%7D%7D%7B%5Cdownarrow%20%7D%7D%7Ba_n%7D%5Cqquad%20%5Cqquad%20%5Cstackrel%7B%5Cstackrel%7B%5Ctextit%7Bthe%20term%20before%20it%7D%7D%7B%5Cdownarrow%20%7D%7D%7Ba_%7Bn-1%7D%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Bcurrent%20term%7D%7D%7Ba_5%7D%5Cqquad%20%5Cquad%20%5Cstackrel%7B%5Ctextit%7Bterm%20before%20it%7D%7D%7Ba_%7B5-1%7D%5Cimplies%20a_4%7D~%5Chspace%7B5em%7D%5Cstackrel%7B%5Ctextit%7Bcurrent%20term%7D%7D%7Ba_%7B12%7D%7D%5Cqquad%20%5Cquad%20%5Cstackrel%7B%5Ctextit%7Bterm%20before%20it%7D%7D%7Ba_%7B12-1%7D%5Cimplies%20a_%7B11%7D%7D)
Answer:
(3, 4 )
Step-by-step explanation:
3x - y = 5 → (1)
x + y = 7 → (2)
adding the 2 equations term by term will eliminate y
4x + 0 = 12
4x = 12 ( divide both sides by 4 )
x = 3
substitute x = 3 into either of the 2 equations and solve for y
substituting into (2)
3 + y = 7 ( subtract 3 from both sides )
y = 4
solution is (3, 4 )

- Given - <u>two </u><u>points </u><u>P </u><u>(</u><u> </u><u>5</u><u> </u><u>,</u><u> </u><u>1</u><u>0</u><u> </u><u>)</u><u> </u><u>and </u><u>R </u><u>(</u><u> </u><u>1</u><u>2</u><u> </u><u>,</u><u> </u><u>1</u><u>4</u><u> </u><u>)</u><u> </u><u>on </u><u>the </u><u>c</u><u>artesian </u><u>plane</u>
- To find - <u>distance </u><u>between </u><u>the </u><u>two </u><u>points</u>
<u>Using </u><u>the </u><u>distance </u><u>formula</u> ~

we have ,

<u>substituting</u><u> </u><u>the </u><u>values </u><u>in </u><u>the </u><u>formula </u><u>,</u><u> </u><u>we </u><u>get</u>

hope helpful :)
Answer:
69.94 miles
Step-by-step explanation:
The distance d₁ the first ship moves after 3 hours is 3 hours × 15 miles per hours = 45 miles
The distance d₂ the second ship moves after 3 hours is 3 hours × 12 miles per hours = 36 miles.
The angle the first ship's direction makes in the North-East direction is 90° - 75° = 15°
The angle the second ship's direction makes in the South-West direction = 14°
The distance moved by the two ships form the side of a triangle. The angle, θ between the two ship directions is 14° + 90° + 15° = 119°
Using the cosine rule, we find the distance d between the two ships
d = √(d₁² + d₂² -2d₁d₂cosθ)
= √(45² + 36² -2×45×36cos119°)
= √(2025 + 1296- (-1570.78))
= √(3321 + 1570.78)
= √4891.78
= 69.94 miles
34x-25 is the answer
Explanation in image