Answer: y - 1 = 8 - 2x
Explanation:
Let 2x + y = 7 be [a] & [a] ║ [b]
Since [a] ║ [b], the the gradient (m) of both [a] and [b] are equal ( -2).
The gradient is -2, since 2x + y = 7 ≡ y = -2x + 7
Now, by using the point slope form (y - y₁) = m (x - x₁); where (x₁ , y₁) = (4 , 1)
⇒ [b] → (y - 1) = -2 (x - 4)
→ y - 1 = 8 - 2x
The diagram below is a graph created with Desmos which confirms the answer.