If you wanted to multiply 5 by 7, for example, you could draw a rectangle on squared paper with sides of 5 squares and 7 squares. You could then count the squares inside the rectangle which would give you the area which is the same as 5 times 7.
All we have to do here is to express numbers 40 and 5 in each of equations. Note that first number in brackets is always x coordinate and second number is y coordinate
First equation:
5 = 40*8 false
Second
5 = 5*40 false again
Third:
5 = 40/8 = 5 True
checking for just in case last one:
5 = 40/5 = 8 False
Correct one is C)
To solve the function in terms of x:

find the power of the subscripts of the log

cross multiply the expression

Therefore the correct answer of a = 6x
3.2 m is converted to 320 cm
3375/225=15
13500/15=900 books
The answer is D