I don’t mean to take point but i do not see a picture :(
Heyo!
l believe the answer is D.
hopefully, this helps you!!!
idqfxemo~
First of all, the first power of 'x' is the highest power in the whole equation,
so we only expect one solution.
You said that <span><u>3x+9 = 21+7x </u>
Subtract 3x from each side:
9 = 21 + 4x
Subtract 21 from each side:
-12 = 4x
Divide each side by 4 :
<u>-3 = x </u>
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