Substitution method-- ? !
what is the x-coordinate of the solution for the system of equations?

y - x = 9
10 + 2x = -2y

enter your answer in the box.

x=

chad should not have included the values (1, 2) and (3, 6) because that would mean he only had half a healing card.

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2