Question

Read and analyze the problem.1. Write an expression for the perimeter of a square whose side is 3x – 7.2.What must be added to x2 – 2x + 1 to get 2x2 + 8x + 8?3. What must be subtracted from 3n2 – 18n + 27 to get n2 + 3n + 18?

Answer 1

#1

Since the square has 4 equal sides

Since the perimeter of the square is the sum of the 4 sides, then

`P=4s`

P is the perimeter

s is the length of the side of the square

Since the side of the square is (3x - 7), then

Substitute s by (3x - 7) in the rule above

`P=4(3x-7)`

Multiply 4 by each term of the bracket

`\begin{gathered} P=4(3x)-4(7) \\ P=12x-28 \end{gathered}`

The expression of the perimeter is

`12x-28`

The answer is 12x - 28