Unit+2+journal

2.1: It all depends on getting at least one of the same coordinate points as the other equation. Only then will the two different lines cross each other revealing the solution. If it has more than 1 identical points than your going to have an infinate amount of solutions. Graph 1 had one solution: (4,5), graph 2 had no solutions because the 2 lines were parallel to each other. Graph 3 had 3 solutions because the first 3 points on each line were identical, (-2,-4), (-1,-2.5), (0,-1). You would have an infinate amount of solutions.

2.2: There are 3 methods on finding the solution in a system of equations. There is substitution, combination and solution set. When there are two equations that involves replacing the variables than you should use the substitution method. If there is a system of equations that requires you to add or subtract the two equations than the method you need is combination. When there is a graph with two different lines intersecting each than find the point where they both cross, that's solution set.

2.3: - 1050x - 75y - the y-intercept for function blue is 1000 and the y-intercept for function red is 1050 because thats what they started with. - the slope for the blue function is up 100 and the slope for function red is 75 because each year they both take out that amount of money in store it in the bank. - The blue bank is better because your opening deposit was less than the red bank and the more you deposit at the end of the year the more you earn. The red bank was only greater on the first year and a half. At the end of year one the red bank has $1030, 10 more than the blue bank. -The blue bank because in year 3 i can make more money than the red bank. -yes because if I open up an account when my child is born i would have up until 18 years to save up in the blue bank and will earn morn money than the red bank.