Umm.. I have to see the problems, we might not have the same textbooks so
<h3>
Answer: x-2y = -8</h3>
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Explanation:
Multiply both sides by 2 to clear out the fraction
y = (1/2)x+4
2y = 2[ (1/2)x + 4 ]
2y = 2*(1/2)x + 2*4
2y = x + 8
Then move the x term over to the left side
2y = x+8
2y-x = 8
-x+2y = 8
Optionally we can multiply both sides by -1
-x+2y = 8
-1*(-x+2y) = -1*8
x-2y = -8
This is in standard form Ax+By = C with A = 1, B = -2, C = -8
The reason why I multiplied both sides by -1 was to make A > 0 which is what some textbooks use as convention. Of course -x+2y = 8 is equally valid too.
Answer:
a) 7 weeks b) George's
Step-by-step explanation:
Sally's score can be modeled by 10x+850.
George's score can be modeled by 50x+570.
We can set them equal to each other to see when they intersect.
10x+850=50x+570
40x=280
x=7
If George overtakes her in the 7th week, of course he'll have the higher score in 12 weeks.
Answer:
-11 im pretty sure
Step-by-step explanation:
The correct value of (3cis(pi/6))³ is 27i.
<h3>What is Complex Number?</h3>
Complex numbers are numbers that consist of two parts — a real number and an imaginary number. Complex numbers are the building blocks of more intricate math, such as algebra.
Given the complex number in polar coordinate expressed as
z = r(cos∅+isin∅)
zⁿ = {r(cos∅+isin∅)}ⁿ
According to DeMoivre’s Theorem;
zⁿ = rⁿ(cosn∅+isinn∅)
Given the complex number;
(3cis(pi/6))³
= {3(cosπ/6 + isinπ/6)}³
Using DeMoivre’s Theorem;
= 3³(cos3π/6 + isin3π/6)
= 3³(cosπ/2 + isinπ/2)
= 3³(0 + i(1))
= 27i
Thus, the correct value of (3cis(pi/6))³ is 27i.
Learn more about Complex number from:
brainly.com/question/10251853
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