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3 years ago

The sum of two numbers is 39. Their difference is 21. What are the two numbers?

Mathematics

2 answers:

Yanka [14]3 years ago

6 0

Answer:

30 and 9

Eeexplination;

mrs_skeptik [129]3 years ago

4 0

Answer:

30 and 9

Step-by-step explanation:

x+y=39 , x-y=21

Solve for x:

x+y=39 , x-y=21

x= 30

Substitute x with 30:

(30)+y=39 , (30)-y=21

Solve for y:

y=9

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Step-by-step explanation:

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2 years ago

In the coordinate plane, draw quadrilateral ABCD with A(–5, 0), B(2, –6), C(8, 1), and D(1, 7), then demonstrate that ABCD is a

Len [333]

Answer:

ABCD is a rectangle

Step-by-step explanation:

∵ A = (-5 , 0) , B = (2 , -6) , C = (8 , 1) , D = (1 , 7)

∵ The x-coordinate of the mid-point of AC = (-5 + 8)/2 =3/2

∵ The y-coordinate of the mid-point of AC = (0 + 1)/2 = 1/2

∴ The mid-point of AC = (3/2 , 1/2)

∵ The x-coordinate of the mid-point of BD = (2 + 1)/2 =3/2

∵ The y-coordinate of the mid-point of BD = (-6 + 7)/2 = 1/2

∴ The mid-point of BD = (3/2 , 1/2)

∴ The mid-point of AC = The mid-point of BD ⇒ (1)

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∵ BD = √[(1 - 2)²+(7 - -6)² = √170

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3 years ago

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taurus [48]

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According to this, we can get:

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3 years ago

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Answer:

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2 years ago

Read 2 more answers

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jeyben [28]

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