If the length of a rectangle increases by 4cm and the width increases by 7cm, then the area will increase by 104cm2. At this time, it just becomes a square. What is the area of the original rectangle

If the length of a rectangle increases by 4cm and the width increases by 7cm, then the area will increase by 104cm2. At this time, it just becomes a square. What is the area of the original rectangle

Let the side length of the later square be a, then: the length of the original rectangle is A-4, and the width is A-7. According to the title meaning, it is a & # 178; - (A-4) (A-7) = 104 = = = > A & # 178; - (A & # 178; - 11a + 28) = 104 = = = > A & # 178; - A & # 178; + 11a-28 = 104 = = = = > 11a = 104 + 28 = 132 = = = > A = 12