Chapter 6: Q. 429 (page 636)

In the following exercises, solve.
$2 p^{2} - 11 p = 40$

Short Answer

Expert verified

Answer is $p = 8, p = - \frac{5}{2}$

Step by step solution

Step 1. Given

The quadratic equation is $2 p^{2} - 11 p = 40$

Step 2. Simplify the quadratic equation

$2 p^{2} - 11 p = 40 2 p^{2} - 11 p - 40 = 0 2 p^{2} - 16 p + 5 p - 40 = 0 2 p (p - 8) + 5 (p - 8) = 0 (p - 8) (2 p + 5) = 0$

So,

$p - 8 = 0 p = 8$

and

$2 p + 5 = 0 p = - \frac{5}{2}$

Step 3. Check both the values

Put $p = 8$ in original equation,

$2 p^{2} - 11 p = 40 2 {(8)}^{2} - 11 (8) = 40 128 - 88 = 40 40 = 40$

Now put role="math" localid="1644646082673" $p = - \frac{5}{2}$ in original equation,

$2 p^{2} - 11 p = 40 2 {(- \frac{5}{2})}^{2} - 11 (- \frac{5}{2}) = 40 \frac{25}{2} + \frac{55}{2} = 40 \frac{80}{2} = 40 40 = 40$

Step 4. Required answer

Answer is $p = 8, p = - \frac{5}{2}$

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In the following exercises, solve.
$2 p^{2} - 11 p = 40$

Short Answer

Step by step solution

Step 1. Given

Step 2. Simplify the quadratic equation

Step 3. Check both the values

Step 4. Required answer

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In the following exercises, solve.2p2-11p=40

Short Answer

Step by step solution

Step 1. Given

Step 2. Simplify the quadratic 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

Geometry

Statistics

Mechanics Maths

Applied Mathematics

Calculus

Probability and Statistics

Study anywhere. Anytime. Across all devices.

In the following exercises, solve.
$2 p^{2} - 11 p = 40$