Exercise 6 Page 270

In Part B, we want to find the perimeter of the given rectangle if x=7 feet. To do so, we will substitute 7 for x in one</premium> of the expressions we created in Part A and simplify it. We will use the expression 4x+10. However, because 2(2x+5) is equivalent, we could substitute 7 in this expression, and the answer will be the same. We found that if x=7 feet, the perimeter of the given rectangle is 38 feet.

We want to find the value of x if the perimeter of the rectangle is 26 inches. We already found two expressions that represent this perimeter, 4x+10 or 2(2x+5). We will create an equation to find x. On one side of the equation, we will place 26, and on the other side one of the expressions from the previous parts, 4x+10. 4x+10=26 Finally, we will use the Properties of Equality to solve this equation for x. Let's do it! We found that if the perimeter is 26 inches, the value of x is 4 inches.