Answer:
2
Step-by-step explanation:
Substitute y=2x in the first equation into the second.
The second equation then becomes;
x = -(2x)+6
x = -2x+6
Collectiing like terms, more -2x to the left,
x+2x =6
3x=6
x=
x= 2
Answer: The percent gain was 25%.
Step-by-step explanation:
Given, Cost price of lot = $1,200
Selling price of lot = $1,500
The percent gain = 
⇒ Percent gain =

Hence, the percent gain was 25% based on his purchase.
Here you go. A quick picture to demonstrate the problem. Hope this helps!! <span />
Answer: Each time the pentagon is rotated , it maps back onto itself. There are five values of for which the pentagon maps back onto itself. This is the same as the number of sides of the pentagon.
Answer:scales percent error=3.51%
Step-by-step explanation:
P ercent error = Experimental value - Theoretical value /Theoretical value x 100
Theoretical value = 6255 grams
Experimental value ( use of scale ) = 6475grams
Percent error =(6475- 6255)grams / 6255grams x 100
=220/6255 x 100
=3.51%