8x+9y=-1 x=6-2y Solve the system by using the substitution method.

Expert Answers

An illustration of the letter 'A' in a speech bubbles

Given the equations:

8x+9y = -1...........(1)

x = 6 - 2y ...............(2)

we need solve for x and y.

We will use the substitution method to solve.

We will substitute (2) into (1).

==> 8x+9y = -1

==> 8(6-2y) + 9y = -1

==> 48 - 16y + 9y = -1

==> -7y = -49

Now we will divide by -7

==> y= -49/-7 = 7

==> y= 7

==> x = 6-2y = 6-2(7) = 6 -14 = -8

Then the solution for the system is:

x = -8  and  y= 7

Approved by eNotes Editorial Team

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial