Answer: Yes
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Step-by-step explanation:
The given solution is (2,9) which means x = 2 and y = 9 pair up together.
Replace x with 2 and replace y with 9.
Let's do so for the first equation
y = 3x+3
9 = 3*2+3
9 = 6+3
9 = 9
We get the same thing on both sides, which confirms the first equation.
Now let's check the second equation.
y = x+7
9 = 2+7
9 = 9
This equation is confirmed as well.
Both equations are true when (x,y) = (2,9) which confirms it is indeed the solution to the system.
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If you are a visual learner, then I recommend graphing out the equations using a tool like GeoGebra or Desmos.
The two lines intersect at (2,9) which visually confirms it is the solution.