Solve for x and y: 7y−5x=31 x=4−2y select one: a. x=8,y=−2 b. x=−2,y=3 c. x=−9,y=−2 d. x=3,y=−2

This is a system of equation:

7y - 5x = 31

x = 4 - 2y

Plug in 4 - 2y for x

7y - 5(4 - 2y) = 31

Distribute -5 to both 4 and -2y

7y - 20 + 10y = 31

Simplify

17y - 20 = 31

Isolate the y. Note the equal sign. What you do to one side you do to the other. Do the opposite of PEMDAS.

Add 20 to both sides

17y - 20 (+20) = 31 (+20)

17y = 51

Divide 17 from both sides to isolate the y

17y/17 = 51/17

y = 51/17 or 3

y = 3

Plug in 3 for y in one of the equations.

x=4−2y

x = 4 - 2(3)

Simplify.

x = 4 - 6

x = -2

x = -2, y = 3 is your answer, or B)

hope this helps

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18