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crimeas [40]
3 years ago
10

- If 2x2 + 8y = 121.5 and x2 - 8y = 121.5, then x = 9 6.36 16 7

Mathematics
1 answer:
Natalija [7]3 years ago
4 0

Step-by-step explanation:

2x² + 8y = 121.5

x² - 8y = 121.5

Add the equations together to eliminate the y terms.

3x² = 243

x² = 81

x = 9

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Albert wants to show that tan(theta)sin(theta)+cos(theta)=sec(theta). He writes the following proof:
Nataly_w [17]
We have that
<span>tan(theta)sin(theta)+cos(theta)=sec(theta)
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</span>[sin²<span>(theta)/cos(theta)]+cos(theta)=sec(theta)

</span><span>the next step in this proof
is </span>write cos(theta)=cos²<span>(theta)/cos(theta) to find a common denominator
so

</span>[sin²(theta)/cos(theta)]+[cos²(theta)/cos(theta)]=sec(theta)<span>

</span>{[sin²(theta)+cos²(theta)]/cos(theta)}=sec(theta)<span>

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and 
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6 0
3 years ago
Read 2 more answers
1. Rachel has a fair pyramid with four faces and a spinner with three equal-sized colored sections. What is the probability that
Masja [62]

Answer:

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Step-by-step explanation:

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4 0
2 years ago
The length of the longer leg of a right triangle is 20 inches more than twice the length of the shorter leg. The length of the h
Alex17521 [72]

Answer:

Step-by-step explanation:

Let x represent the length of the hypotenuse.

Let y represent the length of the the shorter leg.

Let z represent the length of the longer leg.

The length of the longer leg of a right triangle is 20 inches more than twice the length of the shorter leg. It means that

z = 2y + 20

The length of the hypotenuse is 22 inches more than twice the length of the shorter leg. It means that

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Therefore,

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4y² + 88y + 484 = 5y² + 80y + 400

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y - 14 = 0 or y + 6 = 0

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The length of the longer side is

(2 × 14) + 20 = 48 inches

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