Solving 4 symbolic simultaneous equation -- please help!

I am trying to use the following code to solve for a b c d in terms on n and t. but i get an error saying:

Reference to non-existent field 'a'.

Error in Shape_builder (line 7)

S.a

clear all; close all; clc;

syms a b c d n t
eqns=[a+b+c+d==0, d==0, a*n^3+b*n^2+c*n+d==t, 3*a*n^2+2*b*n+c==0];
S=solve(eqns);

S.a
S.b
S.c
S.d

Answer 1

[Walter Roberson]

You are not telling solve() which variables to solve for, and it happens to pick c d n t to solve for.

[Omar Khammash]

THANK YOU!