Question

Solve the system of equations and choose the correct answer from the list of options. (4 points)

x − y = 7
y = 3x + 12

Select one:
a. 2 /19 comma 2 / 33
b. negative 2 / 19 comma negative 33 / 2
c. negative 19 / 2 comma negative 33 / 2
d. 19 / 2 comma 33 / 2

Answer 1

c. negative 19 / 2 , negative 33 / 2

Explanation:

x − y = 7

y = 3x + 12

Substitute y = 3x + 12 into x − y = 7

x − (3x + 12) = 7

x - 3x - 12 = 7

-2x - 12 = 7

-2x = 19

x = -19/2

Substitute x = -5/2 into x − y = 7

-19/2 − y = 7

y = -19/2 - 7

y = - 5/2 - 14/2

y = -33/2

Answer:

x = -19/2, y = -33/2