The base length of each square-based prism in the pedestal design is 3cm less than that of the layer immediately below.

a) Write an algebraic expression for the total of the top surface areas of the three prisms used to make the pedestal.

x
x
x
2x+5
2x+5

Please help, i am so stuck.

2 answers

The surface area for each square would be the side multiplied by itself, with the bottom square = x^2.

The second square's surface would be (x-3)^2.

From this, you should be able to determine how to calculate the third square's area.

Then sum these three terms.

I hope this helps. Thanks for asking.
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