Question

What must be added to 16x2−40x+20 to make it a whole square

Answer 1

Answer:

• 5 will bi added to make whole square
• 16x^2-40x+20+5
• 16x^2-40x+25
• (4x-5)^2

Answer 2

Answer:

The number which should be added to 16x2-40x+20 to make it perfect square is

Step-by-step explanation:

Let the number which should be added to 16x²-40x+20 be x

Use the identity[ a-b ]²=a²-2ab+b² here,

16x²-40x+20

[ 4²x² ] - 2[ab] +20

As the 20 is not perfect square add the number by which we should get nearest perfect square. So 16 or 5 should be added

[4²x²]-2[ab]+20+16

[4²x²]-2[ab]+36

[4²x²]-2[ab]+[6²]

[4²x²]-2[4x × 6]+36

[4x-6]²

Second ;

[4²x²]-2[ab]+20+5

[4²x²]-2[ab]+25

[4²x²]-2[ab]+[5²]

[4²x²]-2[4x × 5]+[5²]

[4x-5]²