Click to Chat

1800-1023-196

+91-120-4616500

CART 0

• 0

MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
`        If x2-hx-21=0,x2-3hx+35=0(h>0)has a common root ,then value of h is equal to A 1.  B  2.   C 3. D 4.`
one year ago

Arun
23513 Points
```							► Let 𝑎 be the common roots of:    𝑥² – ℎ𝑥 – 21 = 0 and    𝑥² – 3ℎ𝑥 + 35 = 0 Then by definition of a root, we have the system:    {  𝑎² – ℎ𝑎 – 21 = 0    {  𝑎² – 3ℎ𝑎 + 35 = 0 ► Subtracting second equation from the first yields:    (𝑎² – ℎ𝑎 – 21) – (𝑎² – 3ℎ𝑎 + 35) = 0 – 0    𝑎² – ℎ𝑎 – 21 – 𝑎² + 3ℎ𝑎 – 35 = 0    𝑎² – 𝑎² – ℎ𝑎 + 3ℎ𝑎 – 21 – 35 = 0    0 + 2ℎ𝑎 – 56 = 0    2ℎ𝑎 = 56    𝑎 = 28/ℎ ► Inserting this in the first equation:    𝑎² – ℎ𝑎 – 21 = 0    (28/ℎ)² – ℎ(28/ℎ) – 21 = 0    ← Since 𝑎=28/ℎ    784/ℎ² – 28 – 21 = 0    784/ℎ² – 49 = 0    784/ℎ² = 49    16/ℎ² = 1                             ← Divide both sides by 49     16 = ℎ²                              ← Multiply both sides by ℎ²     ℎ = ±4 ► Now since we are told that ℎ>0, the solution ℎ=-4 is discarded leading to the final conclusion that:    ℎ = 4        ◄ANSWER
```
one year ago
Think You Can Provide A Better Answer ?

## Other Related Questions on Algebra

View all Questions »

### Course Features

• 731 Video Lectures
• Revision Notes
• Previous Year Papers
• Mind Map
• Study Planner
• NCERT Solutions
• Discussion Forum
• Test paper with Video Solution

### Course Features

• 101 Video Lectures
• Revision Notes
• Test paper with Video Solution
• Mind Map
• Study Planner
• NCERT Solutions
• Discussion Forum
• Previous Year Exam Questions

Post Question