Ask Question
28 July, 20:25

Solve using the elimination method.

2r - 5s = - 14

5r + 2s = 23

+4
Answers (1)
  1. 28 July, 20:33
    0
    Since you can't multiply either equation by a single number to make the r's or s's cancel out you need to multiply both equations.

    I'm going to make the r's cancel out by multiplying the top equation by 5 and the bottom by - 2

    5 (2r - 5s = - 14)

    -2 (5r + 2s = 23)

    Once I multiply I have

    10r - 25s = - 70

    -10r - 4s = - 46

    Now add straight down, and you are left with:

    -29s = - 116

    To get s by itself now you need to divide both sides by - 29

    -29s = - 116

    -29 - 29

    And your result is s = 4

    To find the value of r, substitute s = 4 into one of the original equations and solve for r.

    2r - 5 (4) = - 14

    2r - 20 = - 14

    + 20 + 20

    2r = 6

    so r = 3

    So your solution is s=4 and r = 3
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “Solve using the elimination method. 2r - 5s = - 14 5r + 2s = 23 ...” in 📗 Mathematics if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers