Math Problem Statement

The sum of the squares of two numbers is 356 and the difference is 6

Solution

We are tasked with solving for two numbers whose sum of squares is 356 and difference is 6.

Let the two numbers be xx and yy.

  1. From the problem, we have the equations: x^2 + y^2 = 356 \tag{1} x - y = 6 \tag{2}

Step 1: Express xx in terms of yy using Equation (2)

From Equation (2): x = y + 6 \tag{3}

Step 2: Substitute xx from Equation (3) into Equation (1)

Substitute x=y+6x = y + 6 into x2+y2=356x^2 + y^2 = 356: (y+6)2+y2=356(y + 6)^2 + y^2 = 356

Expand (y+6)2(y + 6)^2: y2+12y+36+y2=356y^2 + 12y + 36 + y^2 = 356

Combine like terms: 2y2+12y+36=3562y^2 + 12y + 36 = 356

Simplify: 2y2+12y320=02y^2 + 12y - 320 = 0

Divide through by 2 to simplify further: y^2 + 6y - 160 = 0 \tag{4}

Step 3: Solve the quadratic equation (4)

The quadratic equation y2+6y160=0y^2 + 6y - 160 = 0 can be solved using the quadratic formula: y=b±b24ac2ay = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} Here, a=1a = 1, b=6b = 6, and c=160c = -160.

Substitute into the formula: y=6±624(1)(160)2(1)y = \frac{-6 \pm \sqrt{6^2 - 4(1)(-160)}}{2(1)} y=6±36+6402y = \frac{-6 \pm \sqrt{36 + 640}}{2} y=6±6762y = \frac{-6 \pm \sqrt{676}}{2} y=6±262y = \frac{-6 \pm 26}{2}

Step 4: Calculate the two possible values of yy

y=6+262=202=10y = \frac{-6 + 26}{2} = \frac{20}{2} = 10 y=6262=322=16y = \frac{-6 - 26}{2} = \frac{-32}{2} = -16

Step 5: Find xx for each value of yy

Using x=y+6x = y + 6:

  1. If y=10y = 10, then x=10+6=16x = 10 + 6 = 16.
  2. If y=16y = -16, then x=16+6=10x = -16 + 6 = -10.

Final Answer:

The two numbers are:

  1. x=16x = 16, y=10y = 10, or
  2. x=10x = -10, y=16y = -16.

Do you want a detailed explanation of how the quadratic formula was applied? Here are some follow-up questions for practice:

  1. What happens if the difference between the two numbers changes to 10?
  2. Can you derive a different pair of equations to solve the problem?
  3. What is the geometric interpretation of the sum of squares?
  4. How does the discriminant in the quadratic formula affect the solution?
  5. Can you solve the problem graphically?

Tip: Always verify solutions by substituting them back into the original equations!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Quadratic Equations
System of Equations

Formulas

x^2 + y^2 = 356
x - y = 6
Quadratic formula: x = (-b ± √(b^2 - 4ac)) / 2a

Theorems

Quadratic formula

Suitable Grade Level

Grades 8-10