Can someone help me with these?

What are the sotions to the quadratic equation 9x^2=4

In the field of thermodynamics, rankine is the unit used to measure temperature. one can convert temperature from celsius into rankine using the formula , what is the temperature in celsius corresponding to r degrees rankine? a. 9/5(c - 273) b. 9/5(c + 273) c. 5/9( c - 273) d. 5/9( c + 273)

Two sides of a right triangle measure 2 units and 4 units. what is the area of the square that shares a side with the third side of the triangle?