Math Problem Statement

on a diagram, one angle is labeled with a measure of (x^2 - 6x)° and a second angle is labeled with a measure of (3x+80)°. If these angles are complementary, then what is the value(s) of x?

Solution

To solve for xx, we are given that the two angles are complementary. This means their measures add up to 9090^\circ.

Let the two angles be:

  • First angle: x26xx^2 - 6x
  • Second angle: 3x+803x + 80

The sum of these two angles is 9090^\circ, so we can set up the equation:

(x26x)+(3x+80)=90(x^2 - 6x) + (3x + 80) = 90

Now, simplify and solve for xx:

  1. Combine like terms: x26x+3x+80=90x^2 - 6x + 3x + 80 = 90 x23x+80=90x^2 - 3x + 80 = 90

  2. Subtract 90 from both sides to set the equation equal to zero: x23x+8090=0x^2 - 3x + 80 - 90 = 0 x23x10=0x^2 - 3x - 10 = 0

  3. Now, solve the quadratic equation x23x10=0x^2 - 3x - 10 = 0 by factoring. We look for two numbers that multiply to 10-10 and add up to 3-3. These numbers are 5-5 and 22.

So, the factored form is: (x5)(x+2)=0(x - 5)(x + 2) = 0

  1. Set each factor equal to zero: x5=0orx+2=0x - 5 = 0 \quad \text{or} \quad x + 2 = 0

  2. Solve for xx: x=5orx=2x = 5 \quad \text{or} \quad x = -2

Thus, the possible values of xx are x=5x = 5 and x=2x = -2.

To verify:

  • If x=5x = 5:

    • First angle: 526(5)=2530=55^2 - 6(5) = 25 - 30 = -5^\circ
    • Second angle: 3(5)+80=15+80=953(5) + 80 = 15 + 80 = 95^\circ

    This gives a contradiction since angles cannot be negative, so x=5x = 5 is not a valid solution.

  • If x=2x = -2:

    • First angle: (2)26(2)=4+12=16(-2)^2 - 6(-2) = 4 + 12 = 16^\circ
    • Second angle: 3(2)+80=6+80=743(-2) + 80 = -6 + 80 = 74^\circ

    These two angles add up to 16+74=9016^\circ + 74^\circ = 90^\circ, which satisfies the condition of complementary angles.

So, the only valid solution is x=2x = -2.


Would you like further clarification or have any questions? Here are 5 related questions you can explore:

  1. What is the difference between complementary and supplementary angles?
  2. How do you solve quadratic equations by completing the square?
  3. What is the definition of an angle in geometry?
  4. How can you check the solutions to a system of equations?
  5. How do you apply factoring in solving polynomials?

Tip: Always check the physical meaning of the problem (e.g., angles cannot be negative) to ensure the solution is valid in context.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Quadratic Equations
Complementary Angles

Formulas

Sum of complementary angles: angle1 + angle2 = 90°
Quadratic equation formula: ax^2 + bx + c = 0

Theorems

Property of complementary angles
Factoring method for solving quadratic equations

Suitable Grade Level

Grades 8-10