OK, one way to solve systems of linear equations is using substitution. You have:
x-2y=5 and x=y+2
The first step is to solve for one of the variables (x or y) on the easiest-to-solve equation. However, they have already solved for x in the second equation:
x=y+2
Now substitute y+2 into every x on the other equation:
x-2y=5
(y+2)-2y=5 ;Plug in y+2 into all the x's
y+2-2y=5 ;Distribute the "understood" 1
2-y=5 ;Combine the y's
-y=3 ;Subtract 2 to both sides
y=(-3) ;Divide both sides by -1
Now that you have what y is equal to, plug that back into x=y+2:
x=(-3)+2 ;Plug in -3 for y
x=-1
Your solution for both equations is (-1,-3).
If: x+y = 4 and y = 2x+1 Then: 4-x = 2x+1 => 3 = 3x => 1 = x So by substitution: x = 1 and y = 3
2x-3y=13
-2
how do you use the substitution method for this problem 2x-3y=-2 4x+y=24
2x + 2y = 44x + y = 1There are many methods you can use to solve this system of equations (graphing, elimination, substitution, matrices)...but no matter what method you use, you should get x = -1/3 and y = 7/3.
(2,3)
If: x+y = 4 and y = 2x+1 Then: 4-x = 2x+1 => 3 = 3x => 1 = x So by substitution: x = 1 and y = 3
2x-3y=13
-2
how do you use the substitution method for this problem 2x-3y=-2 4x+y=24
2x + 2y = 44x + y = 1There are many methods you can use to solve this system of equations (graphing, elimination, substitution, matrices)...but no matter what method you use, you should get x = -1/3 and y = 7/3.
This is not Calculus.y=7(Already solved)substiute y=7 into y=8xtherefore 7 = 8xtherefore x = 7/8
x+2(x+3) = 12 x+2x+6 = 12 x+2x = 12-6 3x = 6 x = 2 and y = 5
y=16 x= -4
16
Since the second equation is already solved for "y", you can replace "y" by "9" in the other equation. Then solve the new equation for "x".
You'd need another equation to sub in