Answer: DJ receive 12 requests for hip-hop songs on Friday night.
Step-by-step explanation:
As per given , we have
[tex]\text{(Number of request country songs ) = }2+\dfrac{4}{3}\times (\text{Number of request for hip-hop songs})[/tex]
Let X represents the number of request for hip-hop songs which equation represents the situation .
If they're 18 request for country songs, then
[tex]18=2+\dfrac{4}{3}X\\\\\Rightarrow\ 18-2 =\dfrac{4}{3}X\\\\\Rightarrow\ 16 =\dfrac{4}{3}X\\\\\Rightarrow\ X=\dfrac{3}{4}\times16= 3\times4=12\\\\\Rightarrow\ X=12[/tex]
Hence, DJ receive 12 requests for hip-hop songs on Friday night.