Please answer me .

a. 2x -3

b. 7

Step-by-step explanation:

a. The expression that represents the difference is sales between the two sales will be:

9x - (7x + 3) = 9x - 7x - 3 = 2x - 3

b. What we do here is to simply substitute the value of 5 for x

mathematically, we have to substitute the value of 5 in the expression above

We have this as:

2(5) -3

= 10-3 = 7

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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