I do not know how to get the following answer
reloading image.
The answer that is tehre i think is the right one, but i have no clue...
You have the system $\displaystyle \left\{\begin{array}{lcr}x-y&=&6\\x+y&=&10\end{array}\right.$
Use the method of elimination to solve the system.
Adding the two equations together, we see that the y term canceled out.
So we get $\displaystyle 2x=16\implies x=\dots$
Then substitute this value of x into either equation in the system to find y.
Can you take it from here?
--Chris
Determine the equation that represents the area of the picture:
The dimensions are given to you: $\displaystyle (39-2x)~cm$ by $\displaystyle (26-2x)~cm$
So we see that area is $\displaystyle (39-2x)(26-2x)~cm^2$
However, the area has a value of $\displaystyle 440~cm^2$
Thus, $\displaystyle (39-2x)(26-2x)=440$
Factor out the left side, and then the equation becomes
$\displaystyle 4x^2-130x+1014=440\implies4x^2-130x+574=0$
Solve this quadratic equation.
Can you take it from here?
--Chris