Algebra 1 - Grapes and Cherry dreaded question on MathXL.... hints

The above question may have different numbers than yours....so beware and make the proper adjustments using my hints.

The question says to graph the system so you need to figure out first what the system is.  It also shows you that the x value is "pounds of cherries" and the y value is "pounds of grapes".   So using x for pounds of cherries and y for pounds of grapes create two inequalities. 

The first inequality needs to express that you need at least 4 lbs in all.   So, if you add up all the pounds of cherries and grapes you should have at least 4 lbs (greater than or equal to 4).  

The second inequality needs to express that you can spend no more than $9.  So you add up $4 times the number of pounds of cherries you buy and $1.50 times the number of pounds of grapes you buy.  Those two together should be no more than $9 (less than or equal to 9).  

Write them in equations (not just words) and graph them.  

Remember that if you graph an inequality it will be a solid line when the line is included.  In the case of both inequalities above they include "or equal to" so you use solid lines (not dotted lines).   

Graph the lines and then figure out which way you shade using a point on one side or the other to determine the solution set.   For example, when you graph the first line you select a point either above or below the line.  Select the point (0,0) and plug in 0 for x and 0 for y into the inequality to see if it is true or not.  If it is true shade the side that has the origin included; otherwise, shade the other way. 

I hope this helps.