SOLUTION: solve the system using any algebraic method x+2y=7 3x+5y=17

Question 218708: solve the system using any algebraic method
x+2y=7
3x+5y=17
Found 2 solutions by drj, MathTherapy:
Answer by drj(1380) (Show Source):
You can put this solution on YOUR website!
solve the system using any algebraic method

x+2y=7
3x+5y=17

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION

Solve:
We'll use substitution. After moving 2*y to the right, we get:
, or . Substitute that
into another equation:
and simplify: Error: 'Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. '. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115. Can't call method "invoke_solver" on an undefined value at /home/ichudov/project_locations/algebra.com/templates/Algebra/Solver/PerlSolver.pm line 115.
error_location: 101

I hope the above steps were helpful.

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And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV
Answer by MathTherapy(1424) (Show Source):
You can put this solution on YOUR website!
solve the system using any algebraic method
x+2y=7
3x+5y=17

x + 2y = 7 ------ (i)
3x + 5y = 17 -------(ii)
-3x - 6y = -21 -------(iii)--- Multiplying eq (i) by - 3
-y = - 4---- Adding eq (ii) and (iii)

y = =

Substituting 4 for y in eq (i) to get: x + 2(4) = 7

x + 8 = 7

x = 7 - 8 =

----------
Check
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x + 2y = 7 ------- - 1 + 2(4) = 7 ----- - 1 + 8 = 7 (TRUE)
3x + 5y = 17 ------- 3(-1) + 5(4) = 17 ----- - 3 + 20 = 17 (TRUE)