panjang diagonal diagonal layang layang ABCD masing masing 8 cm dan (x + 2) cm. Jika luasnya 48 cm², maka nilai x adalah...

L = 1/2 × d1 × d2.
48 = 1/2 × 8 × (x + 2).
48 = 4(x + 2).
48 = 4x + 8.

4x = 48 - 8.
4x = 40.
x = 40/4.
x = 10.

L = [tex] \frac{d₁ x d₂}{2} [/tex] 
48 = [tex] \frac{8(x+2)}{2} [/tex]
48 = [tex] \frac{8x+16}{2} [/tex]
48 = 4x+8
40 = 4x
10 = x