While attempting to multiply the expression (3x + 7)" a student made mistakes. Explain and write the correct way.

Answer:

what do u want us to do pls be more clear!

Answer:

Step-by-step explanation:

[tex]\sf 5(x - 10) = 30 - 15x[/tex]

[tex]\sf 5x-50=30-15x[/tex]

[tex]\sf 5x-50+50=30-15x+50[/tex]

[tex]\sf 5x=-15x+80[/tex]

[tex]\sf 5x+15x=-15x+80+15x[/tex]

[tex]\sf 20x=80[/tex]

[tex]\sf \frac{20x}{20}=\frac{80}{20}[/tex]

[tex]\sf x=4[/tex]

Answer:

1st and 3rd answer

Step-by-step explanation:

1st answer - Having a sample that is not random does not allow you to generalize the results of the experiment/study to the population because it is not representative of the population in the first place.

3rd answer - The definition of a random sample is that each member of the population has an equal chance of being selected.

Answer:

see explanation

Step-by-step explanation:

(a)

Given y is inversely proportional to x² then the equation relating them is

y = [tex]\frac{k\\}{x^2}[/tex] ← k is the constant of variation

To find k use any ordered pair from the table.

Using (1, 4 ) , then

4 = [tex]\frac{k}{1^2}[/tex] = [tex]\frac{k}{1}[/tex] ( multiply both sides by 1

4 = k

y = [tex]\frac{4}{x^2}[/tex] ← equation of variation

(b)

When y = 25 , then

25 = [tex]\frac{4}{x^2}[/tex] ( multiply both sides by x² )

25x² = 4 ( divide both sides by 25 )

x² = [tex]\frac{4}{25}[/tex] ( take the square root of both sides )

x = ± [tex]\sqrt{\frac{4}{25} }[/tex] = ± [tex]\frac{2}{5}[/tex]

Since x > 0 then x = [tex]\frac{2}{5}[/tex]

Answer:

Angle a = Angle D

Answer:

A: Angle A  Angle D

Step-by-step explanation:

Answer: almost there

Step-by-step explanation: bring the 2 up

Answer:

S.S.S

Step-by-step explanation:

When three sides of a triangle are respectively equal to three corresponding sides of another triangle, they are said to be congruent .

hope it is helpful to you

Answer:

The value of x is 8

Step-by-step explanation:

Answer:

7.07106781187

Step-by-step explanation:

if its just asking [tex]\sqrt50[/tex]

:D

Answer:

A. -3/5 B. 1/5. C. 0.8.

Step-by-step explanation:

Since A is on the left side of 0, it will be negative, in which -3/5 is the only negative answer on there, so A= -3/5. Since B is on the right side of the 0 it's positive, and it is equal to 1/5 which gets you to 0.20, which will be the value of each line since 1 divided by 5 is equal to 0.20. 0.8 is also known as 0.80 so C will be next to the 1.

Answer:

12

Step-by-step explanation:

sqrt(6*24)

sqrt(144)

sqrt(12*12)

12

Answer:

12

Step-by-step explanation:

6×24=144

Sq. Root of 144=12

Answer:

I think it would be 5,625ft^2?

Step-by-step explanation:

300÷4=75

75×75=5,625

Answer:

volume of a cone formula = V=πr²h/

3

V=3.14(5)²3/3

V≈78.54

Answer:

4 Matches

Step-by-step explanation:

According To the Question,

Now, The Total Matches she plays in that time = [tex]\frac{(Total Time Played)}{(Time On Each Match)}[/tex]

Thus, Total Matches = 52 / 13 ⇔ 4 Matches

Answer:

6h + 1

Step-by-step explanation:

number of hours: h

pay per hour: 30

pay for the hours: 30h

add sales bonus: 30h + 5

1/5 of total above: (1/5)(30h + 5) = 6h + 1

Answer: 6h + 1

Answer:

19.20

Step-by-step explanation: used

a calc

Answer:

? = 15 yards

Step-by-step explanation:

h² + b² = ?²

9² + 12² = ?²

81 + 144

225

√225 = 15

Answer:

Pythagorean theorem

Step-by-step explanation:

You should use the Pythagorean theorem

a^2+b^2 = c^2  where a and b are the legs and c is the hypotenuse

9^2+ 12^2 = ?^2

81 +144 = ?^2

225 = ?^2

Take the square root of each side

sqrt(225) = sqrt(?^2)

15 =?

Answer with step-by-step explanation:

The way the question is worded, this actually shouldn't be correct. The correct answer should be [tex]3:4[/tex].

Because the trapezoids are similar, we can find the ratio of their perimeters by actually just finding the ratio of their sides.

Why?

By definition, the corresponding sides of a polygon are in a constant proportion. The perimeter is simply the sum of all sides of the polygon. Since we're just adding the sides, the proportion will still be maintained.

Therefore, we'll just need to ratio of their corresponding sides. The only two corresponding sides that are marked are [tex]\overline{RS}[/tex] and [tex]\overline{AB}[/tex].

The ratio of [tex]\overline{RS}:\overline{AB}[/tex] is [tex]18:24\implies \boxed{3:4}[/tex].

The reason why it ideally should be [tex]3:4[/tex] and not [tex]4:3[/tex] is because the question states [tex]RTSU\sim ABCD[/tex], which mentions [tex]RSTU[/tex] first, so our answer should follow this respective order. I believe you were marked right anyways because the specific order is not specified, but generally, you want to give your answer respectively by default.

Answer:

Q(1,5)

R(3,-1)

S(0,0)

T(-2,3)

Please give brainiest?

Answer:

12\sqrt{2}

Step-by-step explanation:

To get the hypotenuse, first we need to get the side length of the square

Area of the square = L²

16\sqrt{3} = L²

L = 4×3

L = 12

Using pythagiras theorem to get the hypotenuse

Hyp² = 12²+12²

Hyp² = 144+144

Hyp² = 288

Hyp = \sqrt {288}

Hyp = 12\sqrt{2}

Hence the hypotenuse of the square is 12\sqrt{2}

Answer:

O  A. [tex](-1,2)[/tex]

Step-by-step explanation:

[tex]y=x+3[/tex]

[tex]2=-1+3[/tex]

[tex]2=2[/tex]

[tex]y=-x+1[/tex]

[tex]2=-1+1[/tex]            Since two -x's are being used, x becomes positive!

2 = 1 + 1

2 = 2

Solution: (-1, 2)

Answer:

it will be 603.00

it will. e counted from the right to the left

Answer:

8 1/2

because 3 + 5= 8+ 1/2= 8 1/2

Answer:

x= -2 , y=5

Step-by-step explanation:

(x+3x)/2 = -4

4x/2 = -4

4x= -8

x = -2

(2y+4y)/2=15

6y/2=15

6y=30

y=5

Answer:

[tex]OP=3.6[/tex]

Step-by-step explanation:

Since OP is parallel to LM, the two triangles are similar, because they share all three angles. By definition, the corresponding sides of a similar polygon must be in a constant proportion.

Thus, we have:

[tex]\frac{6}{6+4}=\frac{OP}{6},\\10\cdot OP=36,\\OP=\frac{36}{10}=\boxed{3.6}[/tex]