Math Problem Statement

solve the equation by substitution, 3x+4y = 10, 2x+3y=7

Solution

We are given the system of equations:

  1. 3x+4y=103x + 4y = 10
  2. 2x+3y=72x + 3y = 7

We'll solve this system using the substitution method by expressing one variable in terms of the other and substituting it into the second equation.

Step 1: Solve one equation for one variable.

Let's solve the first equation for xx:

3x+4y=103x + 4y = 10

Isolate xx:

3x=104y3x = 10 - 4y

x=104y3x = \frac{10 - 4y}{3}

Step 2: Substitute this expression for xx into the second equation.

Now substitute x=104y3x = \frac{10 - 4y}{3} into the second equation:

2x+3y=72x + 3y = 7

Substitute:

2(104y3)+3y=72 \left( \frac{10 - 4y}{3} \right) + 3y = 7

Simplify:

2(104y)3+3y=7\frac{2(10 - 4y)}{3} + 3y = 7

208y3+3y=7\frac{20 - 8y}{3} + 3y = 7

Multiply the entire equation by 3 to eliminate the fraction:

208y+9y=2120 - 8y + 9y = 21

Simplify:

20+y=2120 + y = 21

Solve for yy:

y=2120y = 21 - 20

y=1y = 1

Step 3: Substitute y=1y = 1 back into the expression for xx.

Substitute y=1y = 1 into the equation x=104y3x = \frac{10 - 4y}{3}:

x=104(1)3x = \frac{10 - 4(1)}{3}

x=1043x = \frac{10 - 4}{3}

x=63=2x = \frac{6}{3} = 2

Final Answer:

The solution to the system of equations is:

x=2,y=1x = 2, \quad y = 1

Would you like more details or have any questions? Here are some related problems:

  1. Solve using substitution: x+2y=5x + 2y = 5, 3xy=23x - y = 2
  2. Solve by elimination: 5x+2y=125x + 2y = 12, 7x4y=97x - 4y = 9
  3. Solve the system 4x+5y=234x + 5y = 23, 3x+y=93x + y = 9
  4. Find the intersection point of y=2x+3y = 2x + 3 and y=x+1y = -x + 1
  5. Solve 6x+4y=146x + 4y = 14 and x+2y=4x + 2y = 4 by substitution.

Tip: Always simplify one equation for one variable before substitution for an easier process!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Linear Equations
System of Equations
Substitution Method

Formulas

Solving one equation for a variable
Substituting into the other equation

Theorems

None (no specific theorem, based on algebraic manipulation)

Suitable Grade Level

Grades 8-10