Me my last day to turn this in! marking brainliest solving systems of equations by elimination 3) 7x + 3y= 22 4y= 20 4) -2x + y= 10 4x - y= -14

3)

4)

Step-by-step explanation:

3) For this system of equation you already has one variable in the second equation. Therefore, you only need to solve for in the second one and substitute its value into the first equation to calculate :

4) You must add both equations to cancel the variable and solve for . Then, susbstiute the value of this variable into one of the original equations to calculate :

he has 140 chickens because he has 10 times more chickens than ducks and he has 14 ducks so 14*10=140

b is the right answer