Please answer this ty....

Please help, Thanks.

Evgen [1.6K]

Answer:

C

Step-by-step explanation:

49x² + 28xy + 4y² ← is a perfect square of the form

(ax + by)² = a²x² + 2abxy + b²y²

49 = 7² ⇒ a = 7 and 4 = 2² ⇒ b = 2

2ab = 2 × 7 × 2 = 28

Hence

49x² + 28xy + 4y² = (7x + 2y)²

with factor 7x + 2y ⇒ C

8 0

2 years ago

Write an expression for the following situation and solve it. Mr. Simms bought 20 pencils. He used 1/4 of the pencils and then g

Nitella [24]

Hi!
1/4 of 20 pencils are 5 pencils.
Since he gave away 4 pencils,
Total = 5 + 4 = 9
Mr. Simms use and give away total 9 pencils.

4 0

2 years ago

Which of the following cannot be solved using the quadratic formula?

VLD [36.1K]

Answer:

C

Step-by-step explanation:

Quadratic formula is used only to solve the quadratic equations .

Means the equation of the form

$ax^{2} +bx+c=0$

In this the x^2 part is must because that only makes the equation a quadratic.

Looking at the four options given to you , only the option C has the missing x^2 term, which makes it a linear equation and hence the quadratic formula cannot be applied there .

So the right option for your question with the quadratic formula is

option

C

7 0

2 years ago

In how many ways can a committee of 8 sit in a row if the chairman occupies the middle seat??

Rainbow [258]

They can all sit beside the chairman

5 0

2 years ago

Comparing the two ratios 2/4 and 1/2 2/4 is larger

kumpel [21]

Answer:

3.5 : 7 > 1.2 : 2.5.

Step-by-step explanation:

1. Compare the ratios 4 : 5 and 2 : 3.

Solution:

Express the given ratios as fraction

4 : 5 = 4/5 and 2 : 3 =2/3

Now find the L.C.M (least common multiple) of 5 and 3

The L.C.M (least common multiple) of 5 and 3 is 15.

Making the denominator of each fraction equal to 15, we have

4/5 = (4 ×3)/(5 ×3) = 12/15 and 2/3 = (2 ×5)/(3 ×5) = 10/15

Clearly, 12 > 10

Now, 12/15 > 10/15

Therefore, 4 : 5 > 2 : 3.

2. Compare the ratios 5 : 6 and 7 : 9.

Solution:

Express the given ratios as fraction

5 : 6 = 5/6 and 7 : 9 =7/9

Now find the L.C.M (least common multiple) of 6 and 9

The L.C.M (least common multiple) of 6 and 9 is 18.

Making the denominator of each fraction equal to 18, we have

5/6 = (5 ×3)/(6 ×3) = 15/18 and 7/9 = (7 ×2)/(9 ×2) = 14/18

Clearly, 15 > 14

Now, 15/18 > 14/18

Therefore, 5 : 6 > 7 : 9.

3. Compare the ratios 1.2 : 2.5 and 3.5 : 7.

Solution:

1.2 : 2.5 = 1.2/2.5 and 3.5 : 7 =3.5/7

1.2/2.5 = (1.2 ×10)/(2.5 ×10 ) = 12/25 and 3.5/7 = (3.5 ×10)/(7 ×10) = 35/70 = 1/2

[We removed the decimal point from the ratios now, we will compare the ratio]

Now find the L.C.M (least common multiple) of 25 and 2

The L.C.M (least common multiple) of 25 and 2 is 50.

Making the denominator of each fraction equal to 50, we have

= 12/25 = (12 ×2)/(25 ×2) = 24/50 and 1/2 = (1 ×25)/(2 ×25) = 25/50

Now, 25/50 > 24/50

Therefore, 3.5 : 7 > 1.2 : 2.5.

4 0

1 year ago