Thursday Review: Systems of Equations and Inequalities

Which correctly substitutes Equation 1 into Equation 2?  

  $y=-7x-15$  

Currently, Ashley is 3 years older than Beth. In 5 years, Ashley will be twice as old as Beth. What equations could represent this system?

What is the correct result of adding these two equations together? $4x+9y=-28$  
 $-4x-y=28$  

What could you multiply the first equation by to eliminate the y-variables?

 $5x-y=8$  

 $7x+3y=-2$  

You want to mix a 50% solution with a 75% solution to make 20 liters of a 60% solution. What system of equations could represent this system?

What is the solution to the system of equations?

How many solutions does this system have?

When graphing, if the equations have the same slope and same y-intercept, the system will have __________.

Which ordered pair is NOT a solution?

Mr. Greenwood is making wooden duck calls and turkey calls. In one day, he can make no more than 30 calls. He profits $5 from each duck call and $7 from each turkey call. If he wants to profit at least $300 a day, what system of inequalities could help him decide how many calls to make?