Question

What is the first step in solving this system of equations by elimination?

2x – 2y = 5
5x + 2y = 9
A. Subtract the two equations.
B. Add the two equations.
C. Solve for y.
D. Multiply each equation by 2. Please select the best answer from the choices provided

Answer 1

B. Add the two equations.

Explanation:

Lets solve our system of equations step-by-step

Step 1. Add the two equations

2x – 2y = 5 +

5x + 2y = 9

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7x = 14

Step 2. Solve for x in the resulting equation

7x = 14

`x=(14)/(7)`

x = 2

Step 3. Replace the value of x in any of the original equations

2x – 2y = 5

2(2) – 2y = 5

4 – 2y = 5

-2y = 5 - 4

-2y = 1

`y=-(1)/(2)`

We can conclude that the correct answer is: B. Add the two equations.