Question 679322
Rearrange the second equation as y = -3x+7
Substitute into the first equation
8x - (-3x+7) = 19
Distribute the negative
9x + 3x - 7 = 19
12x - 7 = 19
12x = 19 + 7
12x = 26
x = {{{26/12 = highlight_green(13/6)}}}
y = {{{-3(13/6) + 7 = (-13/2) + 7 = (-13/2) + 7(2/2) = -13/2 + 14/2 = highlight_green(1/2)}}}
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Rearrange the first equation as y = 4x + 11
Substitute into the second equation
6(4x+11) + 4x = -3
Distribute the 6
24x + 66 + 4x = -3
combine like terms
28x + 66 = -3
28x = -3 - 66
28x = -69
{{{highlight_green(x = -69/28)}}}
y = {{{4(-69/28) + 11 = (-69/7) + 11 = (-69/7) + 11(7/7) = (-69/7) + (77/7) highlight_green(y=(8/7))}}}
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