Please tell me I put 100 points for this

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

What is the missing reason in the proof? segment addition congruent segments theorem transitive property of equality subtraction property of equality?

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