Question

Y=3x+7 solve this system of equation using any method

Answer 1

Answer:

x=2, y=13

Step-by-step explanation:

In order to get this by addition which is the easiest way for this you want to take both equations

y=3x+7 and y=-4x+21 and move x to the other side of the equation so it is like  4x+y=21 and -3x+y=7 like that now you have to get rid of one of the exponents and the easiest one to get rid of is y so I'm going to multiply -3x+y=7 by negative 1 so it becomes 3x-y=-7 that way the equations value has not changed since I multiplied both sides and now when I add

4x+y=21 and 3x-y=-7 It'll look like

4x+y=21

3x-y=-7          add those It will get rid of the y

then get 7x=14 simplify to get x=2 then you can take -3x+y=7 plug in x and get

-3(2)+y=7 multiply into -6+y=7 then simplify you get y=13