All categories

3 years ago

From the equations 7a = 4 and 7a + 4b = 12, one can conclude that b is?

Mathematics

2 answers:

alexandr402 [8]3 years ago

7 0

If 7a=4
then 7a+4b=12 is equal to
4+4b=12
4-4+4b=12-4
4b=8
4b/4=8/4
b=2

DaniilM [7]3 years ago

5 0

7a=4
7a+4b=12
you substitute 4 in for 7a because it tells you in the first equation that 7a=4
4+4b=12
next you subtract 4 from each side
4b=8
next you divide 4 from each side
b=2
and theres your answer

You might be interested in

A study was conducted to investigate the relationship between maternal smoking during pregnancy and the presence of congenital m

Pachacha [2.7K]

Answer:

a) In the explanation.

b) P=0.09714

c) P=0.0866

d) p=0.208

Step-by-step explanation:

a) The sampling distribution will have this properties:

1 - The sampling distribution of a proportion is equal to the binomial distribution.

2 - The mean of the sampling distribution will be equal to the proportion of the population (0.328).

$\mu=\pi=0.328$

3 - The standard deviation will be equal to the square root of the product of the proportion and its complementary, divided by the sample size.

$\sigma_s=\sqrt{\pi(1-\pi)/n}=\sqrt{0.328*(1-0.328)/25}=0.094$

B) The fraction with sample proportion of 0.45 or higher is

$z=(p-\pi)/\sigma=(0.45-0.328)/0.094=1.298\\\\P(p\geq0.45)=P(z\geq 1.298)=0.09714$

C) The fraction with sample proportion of 0.20 or lower is

$z=(p-\pi)/\sigma=(0.2-0.328)/0.094=-1.362\\\\P(p\leq0.2)=P(z\geq -1.362)=0.0866$

D) The value of p that cuts off the lower 10% of the distribution corresponds to z=-1.28.

Then we have

$z=(p-\pi)/\sigma\\\\p=\pi+z\sigma=0.328+(-1.28)*0.094=0.328-0.120=0.208$

7 0

3 years ago

Factor the expression completely by first taking out a common factor<br> 3x^2 + 27x + 24

Marina CMI [18]

Answer:

=3(x+8)(x+1)

Step-by-step explanation:

3(x^2+9x+8)

3(x^2+8x+1x+8)

3[(x^2+8x)+(1x+8)]

3[x(x+8)+1(x+8)]

=3(x+8)(x+1)

3 0

3 years ago

Heya!

nataly862011 [7]

Answer:

$m\angle QSN=65^\circ$

Step-by-step explanation:

In the given figure, PQRS is a rhombus and SRM is an equilateral triangle.

We are also given that SN⊥RM and that ∠PRS = 55°.

And we want to find the measure of ∠QSN.

Remember that since PQRS is a rhombus, the angles formed by its diagonals are right angles. Let the intersection point of the diagonals be K. Therefore:

$m\angle RKS=90^\circ$

Now, RKS is also a triangle. The interior angles of all triangles must be 180. Thus:

$m\angle RKS+m\angle KSR+m\angle SRK=180$

Substitute in known values:

$90+55+m\angle KSR=180$

Solve for ∠KSR:

$m\angle KSR+145=180\Rightarrow m\angle KSR=35^\circ$

Since SRM is an equilateral triangle, this means that:

$m\angle SRM=m\angle RMS=m\angle MSR=60^\circ$

Note that RNS is also a triangle. Therefore:

$m\angle SRM+m\angle RNS+m\angle NSR=180$

Substitute in known values:

$60+90+m\angle NSR=180$

So:

$m\angle NSR+150=180\Rightarrow m\angle NSR=30^\circ$

∠QSN is the addition of the two angles:

$m\angle QSN=m\angle KSR+m\angle NSR$

Therefore:

$m\angle QSN=35+30=65^\circ$

4 0

3 years ago

Read 2 more answers

PLEASE HELP DUE AT 11:59

mariarad [96]

The answer would be D

4 0

3 years ago

Select the correct answer. The capacity in cubic feet of a cylindrical silo is given by the function C(x), where x is the radius

katrin [286]

Answer:

C. H(x) = 2x+6

Step-by-step explanation:

Volume of the cylindrical silo = Area of its circular base × Height

Volume of the cylindrical silo = πr²×H

If the area of the circular base of the silo is given by the function A(x), the volume is given by C(x) and the height is given by H(x), the formula can be expressed as;

C(x) = A(x) × H(x)

The height of the cylindrical silo will be;

H(x) = C(x)/A(x)

Given C(x) = 6.28x³ + 18.84x² and

A(x) = 3.14x²

H(x) = 6.28x³ + 18.84x²/3.14x²

H(x) = x²(6.28x+18.84)/3.14x²

H(x) = (6.28x+18.84)/3.14

H(x) = 3.14(2x+6)/3.14

H(x) = 2x+6

Hence, the function, H(x) that represents the height of the silo is 2x+6.

4 0

4 years ago