The area of the painting is
[tex]10x^2+26x+12=l\cdot w[/tex]Where, l is length, and w is the width. Then, we have:
[tex]10x^2+26x+12=(5x+3_{})\cdot w[/tex][tex]w=\frac{10x^2+26x+12}{5x+3}[/tex]And we need to divide two polynomials:
Then, the width of the painting is 2x+4