Chapter 6: Q. 434 (page 636)

In the following exercises, solve.
$(3 x - 2) (x + 4) = 12 x$

Short Answer

Expert verified

Answer is $x = 2, x = \frac{- 4}{3}$

Step by step solution

Step 1. Given

The equation is $(3 x - 2) (x + 4) = 12 x$

Step 2. Simplify the equation

$(3 x - 2) (x + 4) = 12 x 3 x^{2} + 12 x - 2 x - 8 = 12 x 3 x^{2} - 2 x - 8 = 0 3 x^{2} - 6 x + 4 x - 8 = 0 3 x (x - 2) + 4 (x - 2) = 0 (x - 2) (3 x + 4) = 0$

So,

$x - 2 = 0 x = 2$

and

$3 x + 4 = 0 x = \frac{- 4}{3}$

Step 3. Check both the values

Put $x = 2$ in original equation,

role="math" localid="1644652574390" $(3 x - 2) (x + 4) = 12 x (3 \times 2 - 2) (2 + 4) = 12 \times 2 4 \times 6 = 24 24 = 24$

True

Now put $x = \frac{- 4}{3}$ in the original equation,

$(3 x - 2) (x + 4) = 12 x (3 \times \frac{- 4}{3} - 2) (\frac{- 4}{3} + 4) = 12 \times \frac{- 4}{3} - 6 (\frac{8}{3}) = - 16 - 16 = - 16$

True

Step 4. Required answer

Answer is $x = 2, x = \frac{- 4}{3}$

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In the following exercises, solve.
$(3 x - 2) (x + 4) = 12 x$

Short Answer

Step by step solution

Step 1. Given

Step 2. Simplify the equation

Step 3. Check both the values

Step 4. Required answer

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In the following exercises, solve.(3x-2)(x+4)=12x

Short Answer

Step by step solution

Step 1. Given

Step 2. Simplify the equation

Step 3. Check both the values

Step 4. Required answer

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Math Textbooks

Applied Mathematics

Mechanics Maths

Decision Maths

Pure Maths

Statistics

Calculus

Study anywhere. Anytime. Across all devices.

In the following exercises, solve.
$(3 x - 2) (x + 4) = 12 x$