It is given that y varies directly with x . Determine the constant of proportionality , k if and . Then write a direction variation equation . Finally determine the value of x , when . x = 9 y = - 3 y = 15

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.

At the beginning of the year, adrian's savings account balance was \$28$28. each week, he deposits another \$15$15 into that account, and he doesn't spend any of his savings. is his savings account balance proportional to the number of weeks since the start of the year?

Ratio of circumference to diameter example plz i need to now what it looks like.