



 
Hi Maria. A rectangle will have four sides: two vertical and two horizontal. There are 6 "spaces", so there are 5 lines between them plus a line on each edge. So there are seven possible vertical lines and seven possible horizontal lines. This means we need to find the number of ways of choosing 2 vertical lines from a group of seven and multiply that by the number of ways of choosing 2 horizontal lines from a group of seven to find the answer. This can be written in two common forms: Can you take it from here? Cheers,  


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