For example, a(b+c) =a*b+a*c, which means that item A must be multiplied by the next two items B and C.
For example: 2*(3+4)=2*3+2*4.
2*(3+4)=2*7= 14 (this is the original way, multiply first and then divide, then add and subtract, and add first in brackets).
2*3+2*4=6+8= 14 (this method is called the distribution law of multiplication because the brackets in the title are removed and the answer is the same as the original answer).
This problem is more advanced, that is, (a+b)(c+d)=a*c+a*d+b*c+b*d (in other words, each term should be multiplied by each other).
So (a-2)? (a-3)
=a*a-a*3-2*a+2*3
=a*a-3a-2a+6
=a*a[ or it can be written as the square of a (a 2)]-5a+6
Let the side length of a small square be b and the side length of a large square be a,
Because: 4* triangle area+small square area =