Question 641963
You need to start with the formula for the perimeter, p, of a rectangle, which in term of the lenght, L, and width, W, is
(1) p = 2*L + 2*W or
(2) p = 2*(L + W)
Now substitute the expressions for L = x + 3, and W = 2*x -6, into (2) and obtain
(3) p = 2*(x + 3 + 2x - 6), which simplifies to
(4) p = 2*(3x - 3)
Now use the value of p given for your problem and get
(5) 2*(3x - 3) = 26
Divide both sides by 2 yields
(6) 3x - 3 = 13 or
(7) 3x = 16 and the solution
(8) x = 16/3
Is that the correct value of x? Let's check.
Is (26 = 2*(16/3 + 3 + 2(16/3) - 6))?
Is (26 = 2*(16 + 3 - 6))?
Is (26 = 2*13)?
Is (26=26)? Yes
Answer: x = 16/3