Answer:1. The area is l * w, so just multiply 5x by 5x. Replacing x with 2.2 gets: 
(5 * 2.2) * (5 * 2.2) 
 
11 * 11 
= 121 
 
So, the area of the square when x = 2.2 centimeters is 121 sq cm. 
 
2. The expression for this equation would be: 
6(y + 4) 
 
And using the distributive property on this to get the simplified expression, just multiply both y and 4 by 6. 
 
6 * y + 6 * 4 
6y + 24 
So, your expression is 6y + 24. 
 
3. For this one, let's make y's value 3.5 instead of 3 1/2 to make it easier to solve. 
 
We just use the above expression to solve. 
6 * 3.5 + 6 * 4 
21 + 24 
= 45 
 
So, the area of the rectangle when y = 3 1/2 is 45 sq in. 
 
4. For this last one, let's use the formula w = A/l to form an expression that will represent the width. 
 
w = 8w + 18/2 
 
Now, let's simplify it by dividing 8w and 18 by 2. 
w = 8w/2 + 18/2 
 
w = 4w + 9 
 
So the expression to represent the width of the rectangle is 4w + 9. 
Hope this helped! 
Explanation: