Solve this for 10 points: 2x-3y+4y+2x+9y

How do i make someone brainliest? (if you answer me, i might be able to make you brainliest! )

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab

The birth weights of newborn babies in the unites states follow in a normal distrubution with a mean of 3.4 kg and standard deviation of 0.6 kg. reaserches interested in studying how. children gain weights decide to take random samples of 100 newborn babies and calculate the sample mean birth weights for each sample