You have been asked to solve the system below. what method do you choose and why? 4x + 2y = 9 7x + 5y = -1

Elimination isn't exactly the easiest for this situation. But since the equations are in the same form and not solved for the same variable, I would go with elimination.  (If they were solved for the same variable, I would go with substitution.) It would require me to make a manipulation on both equations.

I would multiply first equation by 5 and second equation by -2.  The reason I would do this is because the y's would have opposite coefficients and when you add opposites you get 0.

The new set of equations would look like this:

20x+10y=45

-14x-10y=2

But I will slope here since we aren't asked to solve it.

Some texts use the term linear combination instead of elimination. They are the same.

answer: when you burn wood, the carbon reacts with the oxygen in the air to create ash and smoke. that is a permanent change you cannot undo that.

step-by-step explanation: