Ask question

Ask question

All categories

3 years ago

9

What value of c makes x2 + 6x + c a perfect square trinomial?

2 answers:

lyudmila [28]3 years ago

7 0

Answer:

c=9

Step-by-step explanation:

$x^2+6x+c$

The given polynomial is a perfect square trinomial.

using completing square method to find the perfect square.

$\Rightarrow x^2+6x+c$

$a^2+2ab+b^2=(a+b)^2$

Now we compare the given polynomial

$a^2+2ab+b^2\rightarrow x^2+2\cdot 3\cdot x+c$

$a^2\rightarrow x^2$

$2ab\rightarrow 2\cdot 3\cdot x$

$b^2\rightarrow c$

2ab=6x

b=3

But $b^2\rightarrow c$

So, c=9

Hence, The value of c is 9 to make perfect square.

Dahasolnce [82]3 years ago

4 0

C = 9

x² + 6x + 9
= (x+3)(x+3)
= (x + 3)²

it is a perfect square trinomial when c is equal to 9

Follow my account. (:

You might be interested in

A teacher places n seats to form the back row of a classroom layout. Each successive row contains two fewer seats than the prece

Alex_Xolod [135]

Answer:

The number of seat when n is odd $S_n=\frac{n^2+2n+1}{4}$

The number of seat when n is even $S_n=\frac{n^2+2n}{4}$

Step-by-step explanation:

Given that, each successive row contains two fewer seats than the preceding row.

Formula:

The sum n terms of an A.P series is

$S_n=\frac{n}{2}[2a+(n-1)d]$

$=\frac{n}{2}[a+l]$

a = first term of the series.

d= common difference.

n= number of term

l= last term

$n^{th}$ term of a A.P series is

$T_n=a+(n-1)d$

n is odd:

n,n-2,n-4,........,5,3,1

Or we can write 1,3,5,.....,n-4,n-2,n

Here a= 1 and d = second term- first term = 3-1=2

Let $t^{th}$ of the series is n.

$T_n=a+(n-1)d$

Here $T_n=n$ , n=t, a=1 and d=2

$n=1+(t-1)2$

⇒(t-1)2=n-1

$\Rightarrow t-1=\frac{n-1}{2}$

$\Rightarrow t = \frac{n-1}{2}+1$

$\Rightarrow t = \frac{n-1+2}{2}$

$\Rightarrow t = \frac{n+1}{2}$

Last term l= n,, the number of term $=\frac{ n+1}2$ , First term = 1

Total number of seat

$S_n=\frac{\frac{n+1}{2}}{2}[1+n}]$

$=\frac{{n+1}}{4}[1+n}]$

$=\frac{(1+n)^2}{4}$

$=\frac{n^2+2n+1}{4}$

n is even:

n,n-2,n-4,.......,4,2

Or we can write

2,4,.......,n-4,n-2,n

Here a= 2 and d = second term- first term = 4-2=2

Let $t^{th}$ of the series is n.

$T_n=a+(n-1)d$

Here $T_n=n$ , n=t, a=2 and d=2

$n=2+(t-1)2$

⇒(t-1)2=n-2

$\Rightarrow t-1=\frac{n-2}{2}$

$\Rightarrow t = \frac{n-2}{2}+1$

$\Rightarrow t = \frac{n-2+2}{2}$

$\Rightarrow t = \frac{n}{2}$

Last term l= n, the number of term $=\frac n2$ , First term = 2

Total number of seat

$S_n=\frac{\frac{n}{2}}{2}[2+n}]$

$=\frac{{n}}{4}[2+n}]$

$=\frac{n(2+n)}{4}$

$=\frac{n^2+2n}{4}$

4 0

3 years ago

Please help ASAP!!!!

snow_tiger [21]

Answer:

8

Step-by-step explanation:

1/4πr² + (2x4) - 1/4πr²

r = 4

8

6 0

3 years ago

Read 2 more answers

How many real number solutions does the equation have

Ksju [112]

You have to find the discriminat b^2 -4ac

If it is > 0, the function has two real solutions
if it is = 0, the function has one real solution
if it is <0, the function has no real solution

6^2 - 4(7)(3) = 36 - 84 = - 48

Answer c. no solution

5 0

3 years ago

The bottom of a ladder must be placed 3 ft from a wall. the ladder is 12 feet long. how far above the ground does the ladder tou

3241004551 [841]

9 feet above the ground, since it has to be 3 feet away from the wall you would have to subtract those 3 feet from the length of the ladder.

6 0

3 years ago

10 cards are numbered from 1 to 10 and placed in a box. One card is selected at random and is not replaced. Another card is then

Rasek [7]

16/100 is the probability Hope this helps

6 0

3 years ago

Read 2 more answers