Key Links The following Problems are from the Key Links workbooks and are practice for the Stanford 9 test.

Key Links You will have 1 practice and 2 test grades. You will get to correct you first test grade to get a better grade after redoing the test.

Key Links 1.) Plug in the 30 mph and then the 40 mph and find the difference. 120 - 75 = 45 (B)

Key Links 1.) y = x + x2/20 y = 40 + 80 y = 30 + 45 y = 120 y = 75 Difference = 45

Key Links 2.) In this problem remember that you can’t solve 1 equation with 2 variables, you need 2 equations. So…. You are just looking for 1 of the equations that you might be able to use to solve the 2 equations for x and Y. That’s why there is no equation that handles the fact that there were 4 times the amount of student tickets sold.

Key Links 2.) 3.2x + 2y = 2800 y = 4x so….. 3.2x + 2(4x) = 2800 x = 250 so… y = 1000

Key Links 3.) Plug 24 in for h in the equation and simplify the radical.

Key Links 3.) d = 1.5h d = 1.5(24) d = 36 d = 6

Key Links 4.) Solve for x to find the Max # of sacks in the truck.

Key Links 4.) 1500 + 100x 16,000 100x 14,500 x 145

Key Links 5.) Skip 6.) Work backwards by plugging in the table of values to find the 1 equation that is true in ALL cases.

Key Links 6.) d = n(n-3)/2 0 = 3(3-3)/2 2 = 4(4-3)/2 5 = 5(5-3)/2 9 = 6(6-3)/2

Key Links 7.) Find the correct line by eliminating all those the are negative sloping lines and then use Rise / Run.

Key Links 7.) C y = 5/3x + 0 Y rise = 5 run = 3 X

Key Links 8.) Eliminate 2 then make a table.

Key Links 8.) y = (x-1)2 +2 3 = (0-1)2 +2 plug in(0,3) 3 = 3 2 = 2

Key Links 8.) cont… y = (x-1)2 +2 3 = (2-1)2 +2 plug in(2,3) 3 = 3 So…. y = (x-1)2 +2 is the correct equation for the graph..

Key Links 9.) Find the areas of each smaller part of the bigger Rectangle. 111 1 x x2 +x+x+x+x+x+x+x+1+1 +1+1+1+1+1+1+1+1+1+1 = x2 +7x + 12 x x x2 x x x x 1 1 1 1 1 x 1 1 1 1 1 x 1 1 1 1 1

Key Links 9.) (x + 3)(x + 4) x2 + 3x + 4x + 12 x2 + 7x + 12 111 1 x x

Key Links 10.) Convert to inequality signs. x < 100 y > 10 Use the greatest possible value for x (99) and the smallest possible value for y (11). Then find the one that must be true.

Key Links 11.) Create 2 equations 2x + 2y = 34 x - 2y = 2 Then use linear combination to solve.

Key Links 11.) 2x + 2y = 34 x - 2y = 2 3x = 36 x = 12 2(12) + 2y = 34 2y = 10 & y = 5

Key Links 12.) x - y = 6 2x - 2y = 8 y = x - 6 y = x - 4 Y y = -x + 2

13.) 2x - y > 6 2x + 3y < 18 y < 2x - 6 y < -2/3x + 6 Key Links 13.) 2x - y > 6 2x + 3y < 18 y < 2x - 6 y < -2/3x + 6 2x + 3y < 18 Y X Shaded Area 2x - y > 6

Key Links