SOLUTION: Solve each system by substitution. Determine whether the equations are independent, dependent, or inconsistent, can someone please help me solve this equation y= -4x-7 y= 3x

Algebra ->  Linear-equations -> SOLUTION: Solve each system by substitution. Determine whether the equations are independent, dependent, or inconsistent, can someone please help me solve this equation y= -4x-7 y= 3x      Log On


   



Question 246646: Solve each system by substitution. Determine whether the
equations are independent, dependent, or inconsistent, can someone please help me solve this equation
y= -4x-7
y= 3x

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
y= -4x - 7
Since y = 3x we can write the 1st equation:
3x = -4x - 7
add 4x to each side
3x + 4x = -7
7x = -7
Divide both sides by 7
x = %28-7%29%2F7
x = -1
:
Find y:
y = 3x
y = 3(-1)
y = -3
:
Check solution in 1st equation, substitute for x and y
y = -4x - 7
-3 = -4(-1) - 7
-3 = +4 - 7
:
x is the independent variable
y is the dependent variable