Select the best possible first step to solving the system by first eliminating the y variable. 4x – 5y = 4 3x + 2y = –20 a. none of the above b. multiply the first equation by 2 and multiply the second equation by 5. c. multiply the first equation by 2 and multiply the second equation by –5. d. multiply the first equation by –2 and multiply the second equation by 5.

 Option B is the correct answer.

Explanation:

 We have equations

        4x – 5y = 4   equation 1

        3x + 2y = –20   equation 2

 Now we are eliminating y.

     equation 1 x 2 gives

         8x - 10y = 8   equation 3

    equation 2 x 5 gives

         15 x + 10 y = -100   equation 4

   Now adding equation 3 and equation 4

           8x - 10y + 15 x + 10 y = 8 - 100

            23 x = -92

 So, y got eliminated

 Here we multiplied the first equation by 2 and multiply the second equation by 5 to eliminate y.

Option B is the correct answer.