What is this answer to the following equation: -7=-1 +8x - 6

A) if $50000 is invested in a bank account that pays 9.3% of interest compounded on a six-monthly basis, how much money will be in the account after 3 and 12 years? b) if matusalen's father had put $2.0 in the bank when he was born and there, how long would matusalen have had to his death (969 years later) if the interest was 7% per year composed each month and weekly?

Ineed with number 6 , explain how to get 1978

Y=21.95x+10 y=22.45x solve by substitution