Question 622532
Hi, there--
.
Solve the following system of equations and state if any lines are parallel.
y + 7x + 6 = 0
y = 2x + 30
.
We can solve this using the substitution method. Substitute 2x+30 for y in the first equation.
y + 7x + 6 = 0
(2x + 30) + 7x + 6 = 0
.
Simplify and solve for x.
9x + 36 = 0
9x = -36
x = -36/9
x = -4
.
Substitute -4 for x in the second equation.
y = 2x + 30
y = 2(-4) + 30
.
Simplify and solve for y.
y = -8 + 30
y = 22
.
The solution to this system is the ordered pair (-4, 22). The lines are not parallel.
.
It's always a good idea to check the solution in both equations.
y + 7x + 6 = 0
(22) + 7(-4) + 6 = 0
22 + -28 + 6 = 0
0 = 0 Check!
.
y = 2x + 30
(22) = 2(-4) + 30
22 = -8 + 30
22 = 22 Check!
.
Hope this helps! Feel free to email if there is any part you'd like to explain better.
.
Ms.Figgy
math.in.the.vortex@gmail.com