Answer:
x = 7
Step-by-step explanation:
Start by solving for [tex](y+x)^2[/tex] which is a common expression for both equations. Then in the first equation:
[tex]3\,x5\,(y+x)^2=16\\3x-16=5\,(y+x)^2\\(y+x)^2=\frac{3\,x-16}{5}[/tex]
and in the second equation:
[tex]4\,x+2\,(y+x)^2=30\\2\,(y+x)^2=30-4\,x\\(y+x)^2=15-2\,x[/tex]
Now we make the two [tex](y+x)^2[/tex] expressions equal so we get:
[tex]\frac{3\,x-16}{5} =15-2\,x\\3\,x-16=75-10\,x\\13\,x=75+16\\13\,x=91\\x=7[/tex]
