10. Infinitely many solutions:
Simplify this equation:
When 
the equation becomes
This equality is true for all x, thus the equation has infinitely many solutions.
11. The equation 
should have one solution x=-1.
First, simplify the equation:
This equation will have solution x=-1 when
Therefore, the initial equation is
12. The equation 
should have infinitely many solutions.
Simplify it:
When 
this equation will have infinitely many solutions.
40(12.62) + 7(12.62(1.5)) = 504.80 + 7(18.93) = 504.80 + 132.51 =
637.31 <===
If $1.60 is 1 pound, divide the $ amount by 1.60 to find the number of pounds. 150/1.6 = 93.75
12+.60+ 12.60
12.60*20%
12.60*.20= 2.52
Tip should be around $2.52
Hope this helped :)
