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3 years ago

Dear Sir/ Ma'am,

Mathematics

1 answer:

kondaur [170]3 years ago

4 0

Answer:

$150

Step-by-step explanation:

Let n = the number of students and

Let x = the contribution per student.

We have two conditions:

(1) 12 900 = nx

(2) 12 900 = (n+14)(x - 21)

Set (1) = (2) nx = (n+14)(x - 21)

Remove parentheses: nx = nx - 21n + 14 x - 294

Subtract nx from each side 0 = -21n + 14x - 294

Divide each side by -7 (3) 0 = 3n - 2x + 42

Divide each side of (1) by x (4) n = 12 900/x

Substitute (4) into (3) 0 = (3 × 12 900)/x - 2x + 42

0 = 38 700/x - 2x + 42

Multiply each side by x 0 = 38 700 - 2x² + 42x

Multiply each side by -1 0 = 2x² - 42x - 38 700

Solve the quadratic equation

x = [-b±√(b² - 4ac)]/(2a)

x = {42 ± √[(42² - 4×2(-38700)]}/(2 × 2)

= [42 ± √(1764 +309 600]/4

= [42 ± √(311 364)]/4

= (42 ± 558)/4

= 600/4

= 150

Each student contributes $150.

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Answer:

see attachment for graph

Step-by-step explanation:

< or > : dashed line

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> or ≥ : shade above the line

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Rewrite the equation as: y = 3x - 2

Find two points on the line:

when x = 0, y = 3(0) - 2 = -2 → (0, -2)

when x = 3, y = 3(3) - 2 = 7 → (3, 7)

Plots the found points (0, -2) and (3, 7).

Draw a straight, dashed line through the points.

To graph the line y ≥ -x + 3

Rewrite the equation as: y = -x + 3

Find two points on the line:

when x = 0, y = -(0) + 3 = 3 → (0, 3)

when x = 3, y = -(3) + 3 = 0 → (3, 0)

Plots the found points (0, 3) and (3, 0).

Draw a straight, solid line through the points.

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2 years ago

Read 2 more answers

a mixture of peanuts and corn sells for P40 per kilo. The peanuts sell for P42 per kilo while the corn sells for P36 per kilo. h

Lelu [443]

Answer:

The weight of peanuts in the mixture = 8 kg

The weight of corns in the given mixture = 4 kg

Step-by-step explanation:

Let us assume the weight of peanuts in the mixture = x kg

The weight if corns in the given mixture = y kg

Total weight = (x + y) kg

The combined mixture weight = 12 kg

⇒ x + y = 12 ..... (1)

Cost of per kg if mixture = $ 40

So, the cost of (x + y) kg mixture = (x+y) 40 = 40(x+ y) ..... (2)

The cost of 1 kg of peanuts = $ 42

So cost of x kg of peanuts = 42 (x) = 42 x

The cost of 1 kg of corns = $ 36

So cost of y kg of corns = 36 (y) = 36 y

So, the total cost of x kg peanuts + y kg corns = 42 x + 36 y .... (3)

From (1) and (2), we get:

40(x+ y) = 42 x + 36 y

x + y = 12 ⇒ y = 12 -x

Put this in 40(x+ y) = 42 x + 36 y

We get:

40(x+ 12 -x) = 42 x + 36 (12 -x)

480 = 42 x + 432 - 36 x

or, 480 - 432 = 6 x

or, x = 8

⇒ y = 12 -x = 12 - 8 = 4

⇒ y = 4

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3 years ago

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Answer:

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Step-by-step explanation:

Considering the given figure the sides 'b' , '2' and '5' are making the sides of a right angled triangle in the top right corner of the square, where

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Implementing the values in the formula:

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Nonamiya [84]

Answer:

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Step-by-step explanation:

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