Question 88885
"Solve by any convenient method :
4x + 12y = 24
2x + 6y = 12 "


Lets solve by substitution:


*[invoke solving_linear_system_by_substitution 4, 12, 24, 2, 6, 12]


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"Solve by any convenient method :
8x + 4y =7
x = 2-2y "


Lets solve by substitution:


{{{8(2-2y)+4y=7}}} Plug in {{{x=2-2y}}}


{{{16-16y+4y=7}}} Distribute


{{{16-12y=7}}} Combine like terms


{{{-12y=-9}}} Subtract 16 from both sides


{{{-12y=-9/-12}}} Subtract


{{{y=3/4}}} Reduce



{{{x=2-2(3/4)}}} Now plug in {{{y=3/4}}}


{{{x=2-3/2}}} Multiply


{{{x=1/2}}} Combine like terms


So we have {{{x=1/2}}} and {{{y=3/4}}}

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"Solve by Elimination :
2x -3y =-1
3x + y +15 "


*[invoke solving_linear_system_by_elimination 2, -3, -1, 3, 1, 15]


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"Solve by Substitution :
3x + 8y = 7
x- 4y =9"


*[invoke solving_linear_system_by_substitution 3, 8, 7, 1, -4, 9]