Expert: Richard J. Raridon - 7/11/2006

Question
These are some problems that I've difficulty solving, please help.

1. Solve: 6x+4(3x-2)=6x+2

2. Factor completely: 10x^2+10x-200

3. A 3 foot pole casts a shadow of 9 feet. How tall is a tree with a shadow 0f 12 feet?

4. Add 8a-6 and 4a+5

5. Stan invested $5,000, part at 8% and part at 17%. If the total interest at the end of the year $490, how much did he invest at 8%?

Answer
1. Just multiply out and collect terms
6x +12x -8 = 6x +2 so 12x = 10 and x = 5/6
2. 10(x+5)(x-4)
3. 3/9 = x/12, solve for x
4. 12a-1, is that so hard?
5. let x = amt. invested at 8% and y = amt. invested at 17%
then x+y = 5000 and 0.08x +0.17y = 490, solve for x