In "9 years" there will be at least 31 million homes with these devices
According to the question,
The equation is:
At least 31 million homes,
then,
→ [tex]3x+4 \geq 31[/tex]
By subtracting "4" from both sides of the equation,
→ [tex]3x+4-4 \geq 31-4[/tex]
→ [tex]3x \geq 27[/tex]
→ [tex]x \geq \frac{27}{3}[/tex]
→ [tex]x \geq 9[/tex]
Thus the answer above is appropriate.
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