10.9k views
1 vote
Solve the following system of equations by the substitution method. 8x = 2y + 5 3x = y + 7 What is the solution set?

User Coltuxumab
by
8.3k points

2 Answers

5 votes

Answer:

{(-9/2, -41/2)}

User Resu
by
8.6k points
3 votes
8x = 2y + 5
3x = y + 7 so y = 3x - 7
substitive y = 3x - 7 into 8x = 2y + 5

8x = 2y + 5
8x = 2(3x - 7) + 5
8x = 6x - 14 +5
2x = -9
x = -4.5

y = 3x - 7
y = 3(-4.5) - 7 = -13.5 - 7 = -20.5

solutions (-4.5, -20.5)


User Chris Poe
by
7.9k points