This sequence is arithmetic, because each number is the last number plus two.
5x(2y-3)-(y+8)=13 I believe this is correct
Rewrite the second equation in same form as the first So we have
c + 4d = 8
c - 4d = -6 Now add:-
2c + 0 = 2
2c = 2
c = 1
Now substitute c = 1 in the first equation:-
1 + 4d = 8
4d = 7
d = 7/4 = 1 3/4
Answer c = 1 and d = 1 3/4 Answer