Can someone please explain it to me why the part b is wrong???!!! This is physical application ASAP?!!!!

A spring on a horizontal surface can be stretched and held 0.5 m from its equilibrium position with a force of 35 N. a. How much work is done in stretching the spring 3.5 m from its equilibrium position? b. How much work is done in compressing the spring 1.5 m from its equilibrium position? . . .. . 3.5 (70x) dx 0 (Type exact answers.) The amount of work done is 428.75 J. (Simplify your answer.) b. Set up the integral that gives the work done in compressing the spring 1.5 m from its equilibrium position. Use decreasing limits of integration. 1.5 - 70x(35x)2 dx 0 (Type exact answers.)