Ok from my math knowledge here is what I believe is the answer for each of these:
1) elimination: because you can just multiply the bottom equation (both sides of it!) by 2, and so eliminate the y variable. and from there it's easy to solve for x, and then you can use the answer for x to find y by substitution into one of the equations.
2) substitution: because you can see that it's easy to solve for either x OR y. and once you have the equation for either x= something or y= something you can just substitute that into one of the equations.
Answer:
In classical mathematics, analytic geometry, also known as coordinate geometry or Cartesian geometry, is the study of geometry using a coordinate system. This contrasts with synthetic geometry. Analytic geometry is used in physics, rocket science etc.
Answer:
80%
Step-by-step explanation:
So you basically, just make it a ratio. Since a percentage is out of 100, just make the 5 into 100. To get 5 to 100, you times 20. Then you do the same thing to the 4 which you get 80.
1 is correct bc I asked my teacher