p:l = 5:4 ,luas = 320 cm, berapa a) ukuran b) keliling

Langsung aja y

L = p × l
320 = 5a × 4a
320 = 20a²
a² = 320 : 20
a = √16
a = 4

ukuran
p = 5a = 5 × 4 = 20 cm
l = 4a = 4 × 4 = 16 cm

K = 2(p+l)
K = 2(20+16)
K = 2(36)
K = 72 cm

semoga berguna +_+

320=5x.4x
320=20x²
320:20=x²
16=x²
x=4
P=4x5=20
l=4x4=16

kelilingnya=20+20+16+16=72