49.5k views
4 votes
Solve the system by substitution -4x-3y=-21x=y

User Tibin Paul
by
7.4k points

1 Answer

4 votes

We have the system of equations:


\begin{gathered} -4x-3y=-21 \\ x=y \end{gathered}

We have to solve it by substitution.

The second equation gives the information to substitute, for example, x with y. We perfomr the substitution in the first equation:


\begin{gathered} -4y-3y=-21 \\ -7y=-21 \\ y=(21)/(7) \\ y=3 \end{gathered}

Then, with the value of y and the second equation we have:


x=y=3

Answer: the solution to the system is x=3 and y=3.

User Alextsc
by
8.0k 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