3x/13+4 what is the coefficient in the expression ? edit: its 3x over 13 plus 4

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

If tan2a=cot(a+60), find the value of a, where 2a is an acute angle

Will mark the brainliest. paula makes stained-glass windows and sells them to boutique stores. if her costs total $12,000 per year plus $4 per window for the frame. how many windows must she produce to earn a profit of at least $48,000 in one year if she sells the windows for $28 each?