What is the value of x in the proportion below?

57=x21

Elijah brought a total of 16 pounds of peanuts and cashew nuts and paid $49.50. if peanuts cost $2.75 per pound and cashew nuts cost $3.25 per pound, how many pounds of cashew nuts did he buy?

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?

Ntriangle abc, m∠a = 35° and m∠b = 40°, and a=9. which equation should you solve to find b?