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Alecsey [184]
4 years ago
10

Solve question 3 (a and b) — solve each system of equations by elimination.

Mathematics
1 answer:
Nadya [2.5K]4 years ago
3 0

Answer:

Step-by-step explanation:

hello :

6x+5y=-20.....(*)

-6x-10y=25.....(**)

add(*) and(**) :  -5y=5    so y= -1

multiply (*) by 2   : 12x+10y=-40 ...(***)

now add(**) and (***) : 6x=-15   so x = -15/6 = -5/2

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Find the value of x.<br> 55+5x degrees
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Answer:

If 55 + 5x = 0 then x = -11

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To find x just get it by itself

55 + 5x = 0

subtract 5x

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2/7+2/5=answernin simplest form
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4 years ago
6. Find an exact value. (1 point)
vladimir2022 [97]
<span>6 Find an exact value. 
sin 75°
</span>sin(A+B)=sin(A)cos(B)+cos(A)sin<span>(B)
</span>sin(45)=cos(45)=(2^0.5)/2    sin(30)=0.5      cos(30)=(3^0.5)/2
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the answer is the letter d) quantity square root of six plus square root of two divided by four.

<span>7. Find an exact value. 
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= - sqrt( (1-cos(pi/6) ) / 2) = -sqrt( (1-√3/2) / 2 ) = -(√3-1) / 2√2=(√2-√6)/4
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<span>8. Write the expression as the sine, cosine, or tangent of an angle. 
sin 9x cos x - cos 9x sin x
</span>

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the answer is the letter c) sin 8x

<span>9. Write the expression as the sine, cosine, or tangent of an angle. 
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4 years ago
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