Question

Which shows the correct first step to solving the system of equations in the most efficient manner?

3 x + 2 y = 17. x + 4 y = 19.

x = negative 4 y + 19
x = StartFraction negative 2 y + 17 Over 3 EndFraction
4 y = negative x + 19

Answer 1

x = -4y + 19

Explanation:

We have the two equations 3x + 2y = 17 and x + 4y = 19.

The first step would be to rearrange the variables in the second equation so we have a defined expression for x. We would want to do this so we could then plug in the the defined expression for x into the other equation and solve for the other variable.

x + 4y = 19

We can rearrange this by getting the 4y to the other side.

We can get 4y on the other side by subtracting 4y from both sides

x + 4y - 4y = 19 - 4y

x = -4y + 19

And we have just completed the first step!