Use Substitution to solve the system of equations

Question

y=2x+16

2x-7y=-64

Help!!

Answer 1

Since the first equation says y = 2x + 16, then "y" is exactly the same as "2x + 16" so, wherever you see "y" in the second equation, you can put in "2x + 16" instead of the "y".

The second equation is 2x - 7y = 64 so, instead of writing the "y" you can write "2x + 16":

2x - 7(2x + 16) = 64

Now, distribute the "-7" to the two things inside the parenthesis, combine like terms, and solve for "x".

Once you determine what "x" is, use y = 2x + 16 the determine "y" (by plugging in your "x")

Answer 2

2x -7x = 64, replace 2x with y-16

y-16 - 7y = 64, solve for y

-6y = 80

y = -80/6= -40/3 = - 13 1/3

2x = y-16 = -40/3 -16 = -88/3

x = -44/3 = - 14 2/3