The pair of angles are adjacent angles and supplementary and their measure =180
3(2x+5)(2x-5), 5 is the missing term.
steps
(x) = 5x^2-3x+7
refine
x=5x^2-3x+7
Switch sides
5x^2-3x+7-x=x-x
Subtract x from both sides
5x^2-4x+7=0
Solve with the quadratic formula
