Hey there! 
y = -2x + 19 
y = x + 7 
We gonna solve this system of equation by using the substitution method. 
We wanna solve y = -2x + 19 for y 
Let start by substitute -2x + 19 for y in y = x + 7 
y = x + 7 
-2x + 19 = x + 7 
Subtract x from both sides 
-2x + 19 - x = x + 7 - x 
-3x + 19 = 7 
Now subtract 19 on both sides 
-3x + 19 - 19 = 7 - 19 
-3x = -12 
Then divide both sides by -3
-3x/-3 = -12/-3 
x = 4 
We have the value of x. Now we gonna use that same value to find the value for y. 
We gonna do that by substitute 4 for x in y = -2x + 19 
y = -2x + 19 
y = -2(4) + 19 
y = -8 + 19 
y = 11 
Thus, 
The answer is: x = 4 and y = 11
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