Answer:
I'm not sure but try 13.5.
Step-by-step explanation:
It might not be correct sorry
Answer: ![46x^2+73x+15](https://tex.z-dn.net/?f=46x%5E2%2B73x%2B15)
Step-by-step explanation:
The area of a rectangle can be calculated with the formula:
![A=lw](https://tex.z-dn.net/?f=A%3Dlw)
l: the length of the rectangle.
w: the width of the rectangle.
The area of the remaning wall after the mural has been painted, will be the difference of the area of the wall and the area of the mural.
Knowing that the dimensions of the wall are
by
, its area is:
![A_w=(6x+7)(8x+5)\\\\A_w=48x^2+30x+56x+35\\\\A_w=48x^2+86x+35](https://tex.z-dn.net/?f=A_w%3D%286x%2B7%29%288x%2B5%29%5C%5C%5C%5CA_w%3D48x%5E2%2B30x%2B56x%2B35%5C%5C%5C%5CA_w%3D48x%5E2%2B86x%2B35)
As they are planning that the dimensions of the mural be
by
, its area is:
![A_m=(x+4)(2x+5)\\\\A_m=2x^2+5x+8x+20\\\\A_m=2x^2+13x+20](https://tex.z-dn.net/?f=A_m%3D%28x%2B4%29%282x%2B5%29%5C%5C%5C%5CA_m%3D2x%5E2%2B5x%2B8x%2B20%5C%5C%5C%5CA_m%3D2x%5E2%2B13x%2B20)
Then the area of the remaining wall after the mural has been painted is:
![A_{(remaining)}=A_w-A_m\\\\A_{(remaining)}=48x^2+86x+35-(2x^2+13x+20)\\\\A_{(remaining)}=48x^2+86x+35-2x^2-13x-20\\\\A_{(remaining)}=46x^2+73x+15](https://tex.z-dn.net/?f=A_%7B%28remaining%29%7D%3DA_w-A_m%5C%5C%5C%5CA_%7B%28remaining%29%7D%3D48x%5E2%2B86x%2B35-%282x%5E2%2B13x%2B20%29%5C%5C%5C%5CA_%7B%28remaining%29%7D%3D48x%5E2%2B86x%2B35-2x%5E2-13x-20%5C%5C%5C%5CA_%7B%28remaining%29%7D%3D46x%5E2%2B73x%2B15)
The oldest cousin should be 10. If their ages are consecutive even whole numbers, then the younger cousins should be 2 & 4. 2+4=6+10=16