Ineed to know how to solver this coz i needy grades up

The system is

2x + y = 8
 x  -  y  = 1

Let's solve this system using some of the steps outlined above. 
1.  Solve the first equation for y.  To do this, subtract 2x from both sides:       

      0 + y = 8 - 2x   =>  y = 8 - 2x
2.  Now let's look at the second equation.  See that y?  We  write out the 
      equation like this:    x - (     y     ) = 1
      (Must use those parentheses!)
     Whre you see y, write   8-2x instead:
                                       x - ( 8-2x) = 1
3.   Simplify this:             x  - 8 + 2x = 1
4.     Combine like terms:   3x - 8 = 1;    add 8 to both sides to isolate x:
5.    Isolate x:  3x = 9
6.    Sove for x:     x = 3.  Because x - y = 1, 3 - y = 1, so y must be 2.
7.    Set out the solution:  It's the point (3, 1).

Plese compare this solution with the one giv en in this problem.  Can you find any errors in Jenny's approach?  Please respond. 

The answer is 41.7 because 1.39 times 30 is 41.7

Idon’t feel like doing the math but you need to do 2.24 divided by 7