How do I solve this?

Question

A rectangular painting has dimensions x and x + 10. The painting is in a frame of 2in. wide. The total area of the picture and the frame is 900in.². What are dimensions of the painting?

Answer 1

Dimension of painting and frame (x + 4) by (x + 14)

900 = (x + 4)(x + 14)

 

Can you solve for x and answer?