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Setler [38]
2 years ago
14

18.

Mathematics
1 answer:
nikitadnepr [17]2 years ago
3 0

Answer:

B

Step-by-step explanation:

\sin{x}=\frac{5}{13}, \cos{x}=\sqrt{1-(\frac{5}{13})^2}=\frac{12}{13}

\sin{y}=\frac{8}{17}, \cos{y}=\sqrt{1-(\frac{8}{17})^2}=\frac{15}{17}

\cos(x+y)=\cos{x}\cos{y}-\sin{x}\sin{y}\\=\frac{12}{13}\times\frac{15}{17}-\frac{5}{13}\times\frac{8}{17}\\=\frac{140}{221}

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We have seen that isosceles triangles have two sides of equal length. The angles opposite these sides have the same measure. Use
Naddik [55]

Question has missing figure, the figure is in the attachment.

Answer:

The measure of ∠1 is 65°.

The measure of ∠2 is 65°.

The measure of ∠3 is 50°.

The measure of ∠4 is 115°.

The measure of ∠5 is 65°.

Step-by-step explanation:

Given,

We have an isosceles triangle which we can named it as ΔABC.

In which Length of AB is equal to length of BC.

And also m∠B is equal to m∠C.

ext.m∠C= 115°(Here ext. stands for exterior)

We have to find the measure of angles angles 1 through 5.

Solution,

For ∠1.

∠1 and ext.∠C makes straight angle, and we know that the measure of straight angle is 180°.

So, we can frame this in equation form as;

\angle1+ext.\angle C=180\°

On putting the values, we get;

\angle 1+115\°=180\°\\\\\angle1=180\[tex]\therefore m\angle2=65\°-115\°=65\°[/tex]

Thus the measure of ∠1 is 65°.

For ∠2.

Since the given triangle is an isosceles triangle.

So, m\angle1=m\angle2

Thus the measure of ∠2 is 65°.

For ∠3.

Here ∠1, ∠2 and ∠3 are the three angles of the triangle.

So we use the angle sum property of triangle, which states that;

"The sum of all the angles of a triangle is equal to 180°".

\therefore \angle1+\angle2+\angle3=180\°

Now we put the values and get;

65\°+65\°+\angle3=180\°\\\\130\°+\angle3=180\°\\\\\angle3=180\°-130\°=50\°

Thus the measure of ∠3 is 50°.

For ∠4.

∠4 and ∠2 makes straight angle, and we know that the measure of straight angle is 180°.

So, we can frame this in equation form as;

\angle2 +\angle 4 =180\°

Substituting the values of of angle 2 to find angle 4 we get;

65\°+ \angle 4 = 180\°\\\\ \angle 4 = 180\°-65\°\\\\\angle 4= 115\°

Thus the measure of ∠4 is 115°.

For ∠5.

∠4 and ∠5 makes straight angle, and we know that the measure of straight angle is 180°.

So, we can frame this in equation form as;

\angle4 +\angle 5 =180\°

Substituting the values of of angle 4 to find angle 5 we get;

115\°+ \angle 5 = 180\°\\\\ \angle 5 = 180\°-115\°\\\\\angle 5= 65\°

Thus the measure of ∠5 is 65°.

Hence:

The measure of ∠1 is 65°.

The measure of ∠2 is 65°.

The measure of ∠3 is 50°.

The measure of ∠4 is 115°.

The measure of ∠5 is 65°.

6 0
3 years ago
Karin has 461 songs downloaded joe has 123 more songs downloaded than Karin let s=the number of songs joe downloaded
Paul [167]

Answer:

s=461+123

Step-by-step explanation:

123 more is +125, and that's how many songs Joe, s, has.

4 0
3 years ago
Does anybody know what to do here?
Snezhnost [94]

Answer:

m=6

Step-by-step explanation:

38+8m+4=90

42+8m=90

8m=90-42

8m=48

m=6

6 0
3 years ago
HELP ME PLEASE AND THANK YOU..
BlackZzzverrR [31]
220 people per year

2600-1500= 1100/5 = 220
3 0
2 years ago
The LCM of three numbers is 7920 and their GCD is 12. Two of the numbers are 48 and 264. Using factor notation find the third nu
Lelechka [254]

Answer:

The third number is 180.

Step-by-step explanation:

Let the third number be 9x where x is an integer.

48 = 2*2*2*2*3

264 = 2*2*2*3*11

9x = 3*3*x

2*2*2*2*3*3*11*x = 7920y where y is an integer

1584x = 7920y

so x = 7920y / 1584= 5y.

Now the GCD is 12  so x must have  4 as one of its factors.

Also x is a multiple of 5 so it could be 20 then y  would be 4.

If x = 20 then the third number is 9*20 = 180.

This checks out OK.

6 0
3 years ago
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