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1 year ago

PLEASE HELPPP MEEE PLEASEE!!!

Mathematics

1 answer:

vaieri [72.5K]1 year ago

3 0

Step-by-step explanation:

17)

sec(x) = 1/cos(x)

cot(x) = cos(x)/sin(x)

so,

cos(x)/sin(x) × 1/cos(x) = 1/sin(x) = csc(x)

18)

2×sin(x) + 1 = 0

2×sin(x) = -1

sin(x) = -1/2 = -0.5

x = 210° or x = 330°

why ? sin(30°) = 0.5

so, sin(x) = -0.5 means the angles in the 3rd and 4th quadrant (where sine points "down" and is therefore negative). and x is then either 30° more than 180° (210°) or 30° less than 360° (330°).

draw a circle with the coordinate axis through the center. and then try and see.

19)

again the law of sine :

a/sin(A) = b/sin(B) = c/sin(C)

where the sides (a, b, c) are always opposite to the correlated angles (A, B, C).

so, in our case we have

8/sin(A) = 10/sin(58)

sin(A) = 8×sin(58)/10 = 0.678438477...

A = 42.7217403...° ≈ 43°

20)

so, we have 2 sides and the enclosed angle.

the area of the triangle in this case is

1/2 × a×c×sin(B) = 1/2 × 12×8×sin(60) = 48×sin(60) =

= 41.56921938... ≈ 42

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PLEASE HELP!!! A.S.A.P!!

Ksivusya [100]

Answer:

142m

Step-by-step explanation:

This problem can be solved by simply using the pythagorean theorem, as you stated at the beginning of the problem, which is: $a^{2} +b^{2} =c^{2}$

You are given the a side and b side that are needed for this equation, so it's all a matter of plugging in the information you have:

$110^{2} +90^{2} =c^{2}$

$110^{2} =12100$

$90^{2} =8100$

$12100+8100=c^{2}$

$20200=c^{2}$

Now, because the c is still squared, you must take the square root of 20200 in order to get the length of just side c:

$\sqrt{20200}$ ≈142m

7 0

3 years ago

Brianna went to the store to buy some clothes. She bought 9 pairs of pants at $20 per pair of pants, and 11 shirts that cost $15

stealth61 [152]

Answer:

$345 : whichever is closest

Step-by-step explanation:

Pants were $20 each and she bought 9 of them so multiply:

9x20=180

She paid $180 for 9 pants.

Shirts cost $15 each and she bought 11 of them so Mulitply:

15x11=165

She paid $165 for 11 shirts

Add both totals from pants and shirts

165+180=$345

5 0

3 years ago

O is the centre of the circle, EF is a tangent, angle BCE = 28°, angle ACD = 31°

andriy [413]

Answer

a. 28˚

b. 76˚

c. 104˚

d. 56˚

Step-by-step explanation

Given,

∠BCE=28° ∠ACD=31° & line AB=AC .

According To the Question,

a. the angle between a chord and a tangent through one of the end points of the chord is equal to the angle in the alternate segment.(Alternate Segment Theorem) Thus, ∠BAC=28°

b. We Know The Sum Of All Angles in a triangle is 180˚, 180°-∠CAB(28°)=152° and ΔABC is an isosceles triangle, So 152°/2=76˚

thus , ∠ABC=76° .

c. We know the Sum of all angles in a triangle is 180° and opposite angles in a cyclic quadrilateral(ABCD) add up to 180˚,

Thus, ∠ACD + ∠ACB = 31° + 76° ⇔ 107°

Now, ∠DCB + ∠DAB = 180°(Cyclic Quadrilateral opposite angle)

∠DAB = 180° - 107° ⇔ 73°

& We Know, ∠DAC+∠CAB=∠DAB ⇔ ∠DAC = 73° - 28° ⇔ 45°

Now, In Triangle ADC Sum of angles in a triangle is 180°

∠ADC = 180° - (31° + 45°) ⇔ 104˚

d. ∠COB = 28°×2 ⇔ 56˚ , because With the Same Arc(CB) The Angle at circumference are half of the angle at the centre

For Diagram, Please Find in Attachment

4 0

3 years ago

Scott collects hats. He has 65 hats an plans on buying 80 per year.

kicyunya [14]

Answer:

80x+65 2.465 3.865

Step-by-step explanation:

x being the number of years so in ten years he will have 80x10=800+65=865

80x5=400+65=465 so 5 is the number of years it would take

and i do not understand number 1 but i put a formula just in case that was it

7 0

2 years ago

All of the following expressions are equivalent except.___ 2+m m+2 m-(-2) -2-m

Pachacha [2.7K]

Answer:

$\Huge \boxed{-2-m}$

Step-by-step explanation:

2 + m

Rewrite with variable first.

m + 2

Can’t be simplified further.

m - (-2)

Distribute negative sign.

m + 2

-2-m

Rewrite with variable first.

-m - 2

The last expression is not equivalent to m+2.

4 0

2 years ago