Question

y = 3x - 1
y = x - 7
Solve with Substitution

Answer 1

Y = 3x -1. Y = 3x - 1
(-3) Y = x - 7. -3y = -3x + 21

-2y = 20
-2. = -2
Y = - 10

Y = 3x - 1
-10 = 3x - 1
+ 1. + 1
-9. = 3x
3. 3

-3 = x

(-3,-10)

Answer 2

Solution : {y,x } = { -10 , -3 }
Solve the equation [2] for the variable of y
2 . Y = x-7
Plug this in for variable y in the equation [1]
1 (x -7 ) -3x = -1
1 -2x = 6
Solve the equation [1] for the variable x
1 2x =-6
1 x= -3
By now we know this much
Y = x-7
X =-3
Use the x value to solve for y
Y= ( -3 ) -7 = -10