Welcome :: Homework Help and Answers :: Mathskey.com
Welcome to Mathskey.com Question & Answers Community. Ask any math/science homework question and receive answers from other members of the community.

13,400 questions

17,804 answers

1,438 comments

40,057 users

Solving systems of equations by substitution?

0 votes
{3x-2y=5, x+2y=15}
asked Apr 17, 2013 in ALGEBRA 2 by homeworkhelp Mentor

2 Answers

0 votes

Substitution method :

3x - 2y = 5

Add 2y to each side

3x = 5 + 2y

2y = 3x - 5

x + 2y = 15

Substitute 2y = 3x - 5 in the equation x + 2y = 15

x + (3x - 5) = 15

4x - 5 = 15

4x = 20

x = 5

Substitute x = 5 in the equation x + 2y = 15

5 + 2y = 15

2y = 10

y = 5

The solutions of equations : x = 5 and y = 5.

answered Apr 18, 2013 by diane Scholar
0 votes

Substitution method

The equations are 3x - 2y = 5 and x + 2y = 15

Solve the second equation for since the coefficient of x  is 1.

Second equation : x + 2y = 15

x = - 2y + 15

Find the value of by substituting - 2y + 15  for in the First equation.

First equation : 3x -2y = 5

3(-2y + 15) - 2y = 5

-6y + 45 - 2y = 5

- 8y  = - 45 + 5

y = -40/-8

y = 5

Substitute 5 for y in either equation to find the value of x.

Second equation x + 2y = 15

x + 2(5) = 15

x + 10 = 15

x = 15 -10

x = 5

Solution x = 5 and y = 5.

answered Jul 8, 2014 by david Expert

Related questions

asked Feb 12, 2015 in CALCULUS by anonymous
...