SOLUTION: Solve the system by substitution. x − 2y = 4 2x + 3y = 15

Algebra ->  Angles -> SOLUTION: Solve the system by substitution. x − 2y = 4 2x + 3y = 15       Log On


   

Question 932756: Solve the system by substitution.
x − 2y = 4
2x + 3y = 15

Found 2 solutions by rfer, TimothyLamb:
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
x-2y=4
x=2y+4
2x+3y=15
2(2y+4)+3y=15
4y+8+3y=15
7y=7
y=1
-------------
2x+3*1=15
2x=15-3
2x=12/2
x=6
---------------
6-2*1=4
4=4

Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
x - 2y = 4
2x + 3y = 15
---
put the system of linear equations into standard form
---
x - 2y = 4
2x + 3y = 15
---
copy and paste the above standard form linear equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
---
solution by matrix method:
x = 6
y = 1
--
now by substitution:
---
x - 2y = 4
x = 4 + 2y
2x + 3y = 15
2(4 + 2y) + 3y = 15
8 + 4y + 3y = 15
7y = 7
y = 1
x = 4 + 2y
x = 4 + 2
x = 6
---
solution by substitution:
x = 6
y = 1
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php
---