The lines $-2x + y = k$ and $0.5x + y = 14$ intersect when $x = -8.4$. What is the value of $k$?
-2x+y = k and .5x + y = 14 Use the second equation to find y when x = -8.4
.5(-8.4) + y = 14 results in y = 18.2
Sub this into the FIRST equation to comput value for k
-2(-8.4) + 18.2 = k k=35
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