<u><em>Answer:</em></u>
The combined perimeter is 24x + 52 units
<u><em>Explanation:</em></u>
<u>1- Let's get the perimeter of the first rectangle:</u>
The dimensions of the first rectangle are 4x+5 and 2x+7 units
Perimeter of rectangle = 2(length + width)
Perimeter of first rectangle = 2 (4x+5+2x+7)
Perimeter of first rectangle = 2 (6x + 12)
Perimeter of first rectangle = <u>12x + 24 units</u>
<u>2- Let's get the perimeter of the second rectangle:</u>
The dimensions of the second rectangle are 3x+14 and 3x units
Perimeter of rectangle = 2(length + width)
Perimeter of second rectangle = 2 (3x+14+3x)
Perimeter of second rectangle = 2 (6x + 14)
Perimeter of second rectangle = <u>12x + 28 units</u>
<u>3- Finally, let's get the combined perimeter:</u>
Combined perimeter will be the <u>summation</u> of the two perimeters
Combined perimeter = 12x + 24 + 12x + 28
Combined perimeter = <u>24x + 52 units</u>
Hope this helps :)