Expert: Richard J. Raridon - 10/12/2005

Question
I have a few questions please.

1.) for #1, graph the system of equations.
   2y+x=2
    x-y=5

2.) for #2, use substitution to solve.
   3x-2y=-14
    x+3y=-1

3.) for #3, use addition to solve.
   3x+5y=2
   2x-3y=14

4.) for #4, write a system of 2equations and 2variables, then solve.
   Cindy bought 4 hats and 2 pairs of gloves for $20.00. Sally bought 3 hats and 5 pairs of gloves for $22.00. How much did each hat and pair of gloves cost?

5.) Two numbers have a sum of 83 and have a difference of 17. Find the number.

6.) for #6, write in scientific notation.
   348,000

7.) for #7, write in scientifci notation.
   .00976

8.) for #8, write in standard notation.
   1.245 x 10 to the 5th power
  
9.) for #9, write in standard notation.
   4.892 x 10 to the 2nd power

10.) for #10, evaluate.
    (2 x 10 to the 3rd power)(6 x 10 to the 5th power)

11.) for # 11, evaluate.
    -16x to the 2nd power + 10x  when x=(-2)

Thank you so much.  

Answer
1. They're both straight lines.  It only takes two points to draw a straight line.  Pick a value for x, calculate y, and plot (x,y)
2. x=-4, y=1
3. x=4, y=-2
4. 4H+2G = 20 and 3H+5G = 22 so H=4 and G=2
5. x=50, y=33
6. 3.48x10^5
7. 9.76x10^-3
8. 124,500
9. 489.2
10. 1.2x10^9
11. -84