What is the solution to the system of linear equations below 2/5x-y=6 -2x+5y=-30

Y= (2x) /5 - 6step by step(2x)/5 - y = 6- y = -2/5 (x - 15)answer: || y = (2( x - 15 )) /5

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post