Soru

Zorluk: OrtaLinear Equations in One Variable

In the equation below, kk is a constant.

15x2(3xk)=9x+1015x - 2(3x - k) = 9x + 10

If the equation has infinitely many solutions, what is the value of kk?

  1. A
    -5
  2. B
    20
  3. 5Cevap
  4. D
    8

Cevap

The correct value of kk is 55, which makes the equation have infinitely many solutions.
The correct answer is 55 because distributing 2-2 through the parentheses on the left side of the equation yields 15x6x+2k=9x+1015x - 6x + 2k = 9x + 10. Combining the xx terms gives 9x+2k=9x+109x + 2k = 9x + 10. For a linear equation in one variable to have infinitely many solutions, both sides must be identical. Since the coefficients of xx are already equal (9=99 = 9), we set the constants equal to each other (2k=102k = 10), which simplifies to k=5k = 5.

Adım Adım Çözüm

1
Distribute the constant 2-2 to both terms inside the parentheses on the left side of the equation.
15x6x+2k=9x+1015x - 6x + 2k = 9x + 10
Applying the distributive property correctly simplifies the terms inside the parentheses.
2
Combine the like terms of xx on the left side of the equation.
9x+2k=9x+109x + 2k = 9x + 10
Subtracting 6x6x from 15x15x simplifies the left side of the equation to have a single xx term.
3
Set the constant terms on both sides equal to each other to find the condition for infinitely many solutions.
2k=102k = 10
For a linear equation in one variable to have infinitely many solutions, the coefficients of the variable on both sides must be equal, and the constant terms on both sides must also be equal.
4
Solve for kk by dividing both sides of the equation by 22.
k=5k = 5
Isolating the variable kk yields the final value.

Anahtar Kavram

For a linear equation in one variable to have infinitely many solutions, the equation must simplify to an identity where the variable coefficients are equal and the constant terms are equal on both sides of the equation.
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