114k views
3 votes
Solve the systems of equations by substituting
7) -4x+y=6
-5x-y=21

Solve the systems of equations by substituting 7) -4x+y=6 -5x-y=21-example-1

1 Answer

3 votes
We can use substitution to solve this system of equations. We will solve for y in one of the equations and then substitute that expression for y in the other equation. Here's how:

From the first equation, we can solve for y to get y = 4x + 6.

Now we can substitute 4x + 6 for y in the second equation and solve for x:

-5x - (4x + 6) = 21

-5x - 4x - 6 = 21

-9x = 27

x = -3

Now that we have x, we can substitute -3 back into one of the equations and solve for y:

-4(-3) + y = 6

12 + y = 6

y = -6

Therefore, the solution to the system of equations is x = -3 and y = -6.
User Lbt
by
8.5k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories