The figure is made up of three squares: ABCK, DEJK, and FGHJ.
• EF is the distance between vertex E of square DEJK and vertex F of square FGHJ.
• Squares DEJK and FGHJ share vertex J.
• EJ = side of DEJK = 7 cm, and FJ = side of FGHJ = 3 cm.
• E, F, and J lie on the same line. Since F is between E and J: EF = EJ − FJ = 7 − 3 = 4 cm.
Final Answer: EF = 4 cm