Math Problem Statement

Solve the system of equations: x = -y + 5 and -3x + 7y = 45 by substitution.

Solution

The system of equations shown in the image is:

x=y+5x = -y + 5 3x+7y=45-3x + 7y = 45

Step-by-Step Solution (Using Substitution):

  1. Substitute x=y+5x = -y + 5 into the second equation 3x+7y=45-3x + 7y = 45:

3(y+5)+7y=45-3(-y + 5) + 7y = 45

  1. Simplify the equation:

3y15+7y=453y - 15 + 7y = 45

10y15=4510y - 15 = 45

  1. Solve for yy:

10y=45+1510y = 45 + 15

10y=6010y = 60

y=6y = 6

  1. Substitute y=6y = 6 back into the equation x=y+5x = -y + 5:

x=6+5x = -6 + 5

x=1x = -1

Final Solution:

x=1,y=6x = -1, \quad y = 6

Let me know if you'd like more details or have any questions!


Here are 5 related questions for further exploration:

  1. How do you solve a system of equations using the elimination method?
  2. What are the key differences between substitution and elimination methods in solving systems of equations?
  3. Can you solve a system of equations graphically? How does it differ from algebraic methods?
  4. What are some real-life applications of systems of equations?
  5. How do you know if a system of equations has no solution, one solution, or infinitely many solutions?

Tip: Always double-check your substituted values by plugging them back into the original equations to verify correctness!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Systems of Equations
Substitution Method

Formulas

Substitute one equation into another
Simplify and solve the equation

Theorems

Basic substitution method in systems of equations

Suitable Grade Level

Grades 8-10