Please look at the picture. I answered b but it was incorrect.
Please help.
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9514 1404 393
Answer:
d. 14 -3x
Step-by-step explanation:
If you want to substitute for y in the second equation, you must use the first equation to find an expression for y.
3x +y = 14 . . . . . . first equation
y = 14 -3x . . . . . . subtract 3x from both sides
This gives you the expression for y that you want to use for substitution. It matches the expression of choice D.
y = 14 -3x . . . . matches D