The lines $-2x + y = k$ and $0.5x + y = 14$ intersect when $x = -8.4$. What is the value of $k$?
The lines -2x + y = k and 0.5x + y = 14 intersect when x = -8.4 .
So when x = -8.4 , both lines have the same y value.
Let's plug in -8.4 for x into the second equation to find y .
0.5(-8.4) + y = 14
-4.2 + y = 14
y = 18.2
Now we found x and y . Use these values in the first equation to find k .
-2(-8.4) + 18.2 = k
35 = k
The lines -2x + y = k and 0.5x + y = 14 intersect when x = -8.4 .
So when x = -8.4 , both lines have the same y value.
Let's plug in -8.4 for x into the second equation to find y .
0.5(-8.4) + y = 14
-4.2 + y = 14
y = 18.2
Now we found x and y . Use these values in the first equation to find k .
-2(-8.4) + 18.2 = k
35 = k