Test quest and I’m stuck plz help

Use the elimination method to solve the system of equations -x+5y=-4 and 4x+3y=16

The difference of two numbers is 40. find the numbers if 0.3 parts of one number is equal to 37.5% of the other one.

Aculture started with 2,000 bacteria. after 8 hours, it grew to 2,400 bacteria. predict how many bacteria will be present after 19 hours . round your answer to the nearest whole number. p=ae^kt