90-(1/2x+15)=2x-50 what is x?

Me find the missing dimension of a triangle height: 7 in., area: 21^2

Aretha wanted to gather data about the cost of local bowling leagues in her area. she plotted the data and determined that the average bowling league costs consist of a one-time registration fee and a monthly fee modeled by the equation y = 15x + 20. identify and interpret the y-intercept in this model. the y-intercept is 20. this is the cost per month. the y-intercept is 20. this is the cost of registration. the y-intercept is 15. this is the cost of registration. the y-intercept is 15. this is the cost per month.

Consider the sequence below. 3 , 1 , 1/3 , 1/9 , select the explicit function which defines the sequence.