Question

Panjang diagonal belah ketupat secara berturut - turut adl 20 cm da ( 3x + 4 ) cm . jika luas belah ketupat tsb adl 340 cm persegi . tentukan
a. nilai x
b.panjang masing 2 diagonal

Answer 1

Dik :
D1 = 20 cm
D2 = (3X+4)
L = 340 cm

maka :
L = (D1xD2) /2
340 = (20 x (3x+4) ) / 2
340 x 2 = 60x + 80
680 - 80 = 60x
x = 600/60
x = 10 cm

panjang diagonal :
D1 = 20 cm
D2 = (3x+4)
     = 3(10) + 4
     = 34 cm

Answer 2

1/2×20×(3x+4)=340 cm²
60x+80=680
x=10
panjanv diagonal 1=20 cm
panjang diagonal 2=34 cm