What is the conjugate of 7+2√5

i don’t know how to do this please help

What is the area of a triangle with vertices at (-3 3) (-3,2) and (1,2)?

This is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 5 terms.

What is the value of n in the equation -1/2(2n+4)+6=-9+4(2n+1)