Question 954665
x, the width
y, the height
x=16+y, the width description transcribed


The diagonal of 80 inches cuts the rectangle into two congruent right triangles which have side lengths following the Pythagorean Theorem Formula.


{{{x^2+y^2=d^2}}}, d for the diagonal.
{{{(16+y)^2+y^2=80^2}}}


Should be no trouble from there.