luas suatu persegi panjang 48cm jika panjang (x+3)cm dan lebar(2x-4)cm,maka panjang diagonal persegi panjang adalah. tolong pake caranya

(x + 3)(2x - 4) = 48
2x² + 2x - 12
= 48
2x² + 2x - 12 - 48 = 0
2x² + 2x - 60
x² + x - 30 = 0

(x + 6) (x - 5) = 0
x - 5 = 0
x = 5

p = x + 3 = 5 + 3 = 8 cm.
l = 2x - 4 = 2(5) - 4 = 6 cm.

d² = p² + l²
d² = 8² + 6²
d² = 64 + 36
d² = 100
d = √100
d = 10 cm