]> Examples:

Examples:

  1. Find the unique values of variables a, b, and c.

    1a+2b+3c=18.1
    2a-2b+4c=14.2
    3a+5b-2c=6.9

    Equation two minus two times equation one yields 6 b 2 c = 22 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyOeI0IaaGOnaiaadkgacqGHsislcaaIYaGaam4yaiabg2da9iabgkHiTiaaikdacaaIYaaaaa@3E7D@ While equation three minus 3 times equation one becomes b 11 c = 47.4 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyOeI0IaamOyaiabgkHiTiaaigdacaaIXaGaam4yaiabg2da9iabgkHiTiaaisdacaaI3aGaaiOlaiaaisdaaaa@3FEE@ Next, we use these two new equations to solve for the variable c by eliminating b as shown below. 6 b 2 c + 6 ( b 11 c ) = 22 + 6 ( 47.4 ) 64 c = 262.4 c = 4.1 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyOeI0IaaGOnaiaadkgacqGHsislcaaIYaGaam4yaiabgUcaRiabgkHiTiaaiAdacaGGOaGaeyOeI0IaamOyaiabgkHiTiaaigdacaaIXaGaam4yaiaacMcacqGH9aqpcaaIYaGaaGOmaiabgUcaRiabgkHiTiaaiAdacaGGOaGaeyOeI0IaaGinaiaaiEdacaGGUaGaaGinaiaacMcadaGdOaWcbeqaaaGccaGLsgcacaaI2aGaaGinaiaadogacqGH9aqpcaaIYaGaaGOnaiaaikdacaGGUaGaaGinamaaoGcaleqabaaakiaawkziaiaadogacqGH9aqpcaaI0aGaaiOlaiaaigdaaaa@5CC0@ Plugging this value into either of the equations with variable a removed yields b=2.3. Plugging found values for c and b into any of the original 3 equations will cause an outcome of a=1.2.

  2. Find the unique values of variables a, b, and c.

    3a+2b+3c=11.5
    2a-2b-c=1.6
    4a-2b-c=11

    Equation one plus equation two becomes 5 a + 2 c = 13.1 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaGynaiaadggacqGHRaWkcaaIYaGaam4yaiabg2da9iaaigdacaaIZaGaaiOlaiaaigdaaaa@3E03@
    Equation one plus equation three becomes 7 a + 8 c = 22.5 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaG4naiaadggacqGHRaWkcaaI4aGaam4yaiabg2da9iaaikdacaaIYaGaaiOlaiaaiwdaaaa@3E0F@

    Comment: Notice variable elimination order is not important.

    Using these two calculated equations one can solve for a by subtracting four times the first calculated equation from the second calculated equation. 13 a = 29.9 a = 2.3 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyOeI0IaaGymaiaaiodacaWGHbGaeyypa0JaeyOeI0IaaGOmaiaaiMdacaGGUaGaaGyoamaaoGcaleqabaaakiaawkziaiaadggacqGH9aqpcaaIYaGaaiOlaiaaiodaaaa@43D2@ Plugging the a value into either of the calculated equations gives 5 ( 2.3 ) + 2 c = 13.1 c = 0.8 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaGynaiaacIcacaaIYaGaaiOlaiaaiodacaGGPaGaey4kaSIaaGOmaiaadogacqGH9aqpcaaIXaGaaG4maiaac6cacaaIXaWaa4akaSqabeaaaOGaayPKHaGaam4yaiabg2da9iaaicdacaGGUaGaaGioaaaa@4659@ . Finally plugging in numerical values of a and c into any of the original equations gives the result b=1.1.