How would I complete this?

Consider symmetrically placed rectangular insulators with uniformly charged distributions of equal magnitude as shown. x y −−−−−− what is the direction of the net field at the origin?

50 will mark show all use the linear combination method to solve the system of equations. explain each step of your solution. if steps are not explained, you will not receive credit for that step. 2x+9y= -26 -3x-7y=13

Y= a(x-3)squared-1 what is the value of a