Is this relation a function

Brent needs to paint a logo made using two right triangles. the dimensions of the logo are shown below. what is the difference between the area of the large triangle and the area of the small triangle? (1 point) select one: a. 4.5 cm2 b. 8.5 cm2 c. 16.5 cm2 d. 33.0 cm2

The suare root of 9x plus 7 plus the square rot of 2x equall to 7

Can you me find the missing length. i attached an image.