A square has 4 right angels and 4 sides with equal angels ;)
Answer:




Step-by-step explanation:
Given
See attachment for complete question
Required
Match equivalent expressions
Solving (a):

The expression can be written as:
--- 0
---- 1
--- 2
---- 3
---- 4
For the nth term, the expression is:
---- n
So, the summation is:

Solving (b):

The expression can be written as:
--- 0
---- 1
--- 2
---- 3
---- 4
For the nth term, the expression is:
---- n
So, the summation is:

Solving (c):

The expression can be written as:
--- 0
---- 1
--- 2
---- 3
---- 4
For the nth term, the expression is:
---- n
So, the summation is:

Solving (d):

The expression can be written as:
--- 0
---- 1
--- 2
---- 3
---- 4
For the nth term, the expression is:
---- n
So, the summation is:

Answer:
the second one, ((6 x 5) x 4) +((5 x 4) x 2) = 160
the third one, ((7 x 6) x 4) + (6 x 4) x 2) = 216
the fourth one, ((8 x 4) x 4) + ((4 x 3) x 2) = 152
Step-by-step explanation: