Question 1

The table shows four pairs of values of x and y that satisfy the linear equation
y = 3x -5. Find the values for P and S.

Select and check your answer...

A. P=1 and S=7
B. P=7 and S=1
C. P=-1 and S=7
D. P=-7 and S=1

Let's find the value for P first. For the point (2,P), P is the y-coordinate when the x-coordinate is 2. To solve this, use x = 2 to find P by:

    substituting x = 2 , y = P:     P = 3(2)-5

    3 x 2 gives 6                :        = 6 - 5  
 
    6 - 5 gives 1                :        = 1

Therefore P = 1.     

Similarly, now let's find S. For the point (4,S), S is the y-coordinate when the x-coordinate is 4. To solve this, use x = 4 to find P by:

    substituting x = 4 , y = S  :   S = 3(4)-5

    3 x 4 gives 12                 :      = 12 - 5  

    12 - 5 gives 7                 :      = 7

Therefore S = 7.