All categories

2 years ago

90=3(x+8)+2x-4 what is x

Mathematics

2 answers:

nirvana33 [79]2 years ago

8 0

Answer.

x = 14.

Step-by-step explanation:

3(x+8) + 2x - 4 = 90

3x + 24 + 2x - 4 = 90

5x + 20 = 90

5x = 70

x = 70/5

x = 14.

Lilit [14]2 years ago

6 0

Answer:

x = 14

Step-by-step explanation:

Solve for x:

90 = -4 + 2 x + 3 (x + 8)

3 (x + 8) = 3 x + 24:

90 = 3 x + 24 + 2 x - 4

Grouping like terms, 3 x + 2 x - 4 + 24 = (2 x + 3 x) + (-4 + 24):

90 = (2 x + 3 x) + (-4 + 24)

2 x + 3 x = 5 x:

90 = 5 x + (-4 + 24)

24 - 4 = 20:

90 = 5 x + 20

90 = 5 x + 20 is equivalent to 5 x + 20 = 90:

5 x + 20 = 90

Subtract 20 from both sides:

5 x + (20 - 20) = 90 - 20

20 - 20 = 0:

5 x = 90 - 20

90 - 20 = 70:

5 x = 70

Divide both sides of 5 x = 70 by 5:

(5 x)/5 = 70/5

5/5 = 1:

x = 70/5

The gcd of 70 and 5 is 5, so 70/5 = (5×14)/(5×1) = 5/5×14 = 14:

Answer: x = 14

You might be interested in

An airplane travels at an average speed of 250 mph for 3 hours.

expeople1 [14]

250 × 3 = 750

D. 750

And i think i have already answered this one before..

4 0

2 years ago

Read 2 more answers

Find the permeter of a quadrilateral with vertices at C (2,4), D(1,1), E(5,0), and F(3,4). Round your answer to the nearest hund

denpristay [2]

Answer:

12.76

Step-by-step explanation:

This is much easier to solve if you draw it out on a graph. The perimeter is the sum of all the sides. I used the Pythagorean theorem to find the hypotenuse.

${a}^{2} + {b}^{2} = {c}^{2} \\ c = \sqrt{ {a}^{2} + {b}^{2} }$

$dc = \sqrt{ {3}^{2} + {1}^{2} } = \sqrt{10} \\ cf = 1 \\ fe = \sqrt{ {4}^{2} + {2}^{2} } = \sqrt{20} \\ de = \sqrt{ {1}^{2} + {4}^{2} } = \sqrt{17} \\ \sqrt{10} + 1 + \sqrt{20} + \sqrt{17} = 12.76$

7 0

2 years ago

Braden is coaching a youth soccer team, which has eight players. At the end of a tied game, Braden's team must go into a shootou

cupoosta [38]

Randomly select a chip from a bucket containing eight chips, whick are each uniquely labeled with each child's name

8 0

2 years ago

HELP PLEASE!!!!

kumpel [21]

Answer:

The rational numbers are $\frac{11}{3}, 6.25, 0.01045,\sqrt{\frac{16}{81}},0.\bar{42}$ and the irrational functions are $\sqrt{48},\sqrt{\frac{3}{16}}$ .

Step-by-step explanation:

A rational number can be expressed in the form of $\frac{p}{q}$ , where p and q are integers and q is not equal to 0. For example $2,3.5,\frac{2}{5},...$ .

An irrational function can not be expressed in the form of $\frac{p}{q}$ , where p and q are integers and q is not equal to 0. For example $\sqrt{2},\sqrt{3},\sqrt{5},...$ .

If any number is multiplied by a irrational number then the resultant number is an irrational number.

By the above definition we can conclude that:

The number $\frac{11}{3}$ is a rational number.

$\sqrt{48}=\sqrt{16\times 3}=4\sqrt{3}$

Therefore $\sqrt{48}$ is an irrational number.

$6.25=\frac{625}{100}=\frac{25}{4}$

Therefore 6.25 is a rational number.

$0.01045=\frac{1045}{100000}=\frac{209}{20000}$

Therefore 0.01045 is a rational number.

$\sqrt{\frac{16}{81}}=\frac{4}{9}$

The number $\frac{16}{81}$ is a rational number.

$\sqrt{\frac{3}{16}}=\frac{\sqrt{3}}{4}$

The number $\frac{3}{14}$ is an irrational number.

$0.\bar{42}=\frac{42}{99}$

Therefore $0.\bar{42}$ is an irrational number. The numbers with recursive bar are always rational numbers.

3 0

2 years ago

Show that cos(3x) = cos3(x) − 3 sin2(x)cos(x). (Hint: Use cos(2x) = cos2(x) − sin2(x) and the cosine sum

otez555 [7]

<u>Step-by-step explanation:</u>

To prove:

$\cos 3x=\cos^3x-3\sin^2 x\cos x$

Identities used:

$\cos(A+B)=\cos A\cos B+\sin A\sin B$ ......(1)

$\sin 2A=2\sin A\cos A$ ........(2)

$\cos 2A=\cos^2A-\sin^2 A$ .......(3)

Taking the LHS:

$\Rightarrow \cos 3x=\cos (x+2x)$

Using identity 1:

$\Rightarrow \cos (x+2x)=\cos x\cos 2x-\sin x\sin 2x$

Using identities 2 and 3:

$\Rightarrow \cos x(\cos ^2x-\sin^2 x)-\sin x(2\sin x\cos x)\\\\\Rightarrow \cos^3x-\sin^2x\cos x-2\sin^2 x\cos x\\\\\Rightarrow \cos^3x-3\sin^2x\cos x$

As, LHS = RHS

Hence proved

4 0

2 years ago