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Find the solution to the system of equations: x + 3y = 7 and 2x + 4y = 8

1. Isolate x in the first equation:
2. Substitute the value for x into the second equation:
3. Solve for y:
 
 
 
4. Substitute y into either original equation:
5. Write the solution as an ordered pair:
 
 
x = 7 – 3y
2(7 – 3y) + 4y = 8
14 – 6y + 4y = 8
14 – 2y = 8
–2y = –6
y = 3
x + 3(3) = 7

2 Answers

4 votes
1) x= 7 - 3y
2) 2(7 - 3y) + 4y = 8
3) 14 - 6y + 4y =8
14 - 2y = 8
- 14 + 14 - 2y = 8 - 14
2y = 6
y = 3
4) x=7 - 3y = 7 - 3*3 =7 - 9 = -2
5) (-2, 3)
User Wwli
by
6.5k points
4 votes
1. Isolate x in the first equation:
x = 7 – 3y

2. Substitute the value for x into the second equation:
2(7 – 3y) + 4y = 8

3. Solve for y:14 – 6y + 4y = 8
14 – 2y = 8
–2y = –6
y = 3

4. Substitute y into either original equation:
x + 3(3) = 7
x + 9 = 7
x = -2

5. Write the solution as an ordered pair:
(-2 , 3)

hope it helps
User Syam S
by
5.6k points