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2 years ago

The sum of two numbers is 72 and their difference is 40. Using elimination method

Mathematics

1 answer:

d1i1m1o1n [39]2 years ago

3 0

Answer:

here's what we know:

a + b = 72

a - b = 26

We can use the elimination method to solve this problem:

a + b = 72

a - b = 26

---------------

2a = 98

Divide both sides by 2:

a = 49

So we now have:

49 + b = 72

and:

49 - b = 26

Subtract 49 from both sides:

b = 23

and

-b = -23 (multiply both sides by -1) → b = 23

Step-by-step explanation:

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An object is dropped from a small plane. As the object falls, its distance, d, above the ground after t seconds, is given by the

DedPeter [7]

The inequality can be used to find the interval of time taken by the object to reach the height greater than 300 feet above the ground is:

$d = -16t^2 + 1000$

Solution:

The object falls, its distance, d, above the ground after t seconds, is given by the formula:

$d = -16t^2 + 1000$

To find the time interval in which the object is at a height greater than 300 ft

Frame a inequality,

$-16t^2 + 1000 > 300$

Solve the inequality

Subtract 1000 from both sides

$-16t^2 + 1000 - 1000 > 300 - 1000\\\\-16t^2 > -700$

$16t^2 < 700\\\\Divide\ both\ sides\ by\ 16\\\\t^2 < \frac{700}{16}\\\\Take\ square\ root\ on\ both\ sides\\\\t < \sqrt{\frac{700}{16}}\\\\t < \pm 6.61$

Time cannot be negative

Therefore,

t < 6.61

And the inequality used is: $-16t^2 + 1000>300$

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2 years ago

The number of chickens to the the number of ducks on a farm was 6:5. after 63 ducks were sold, there were three times as many ch

Rom4ik [11]

Let x be the common factor between chickens and ducks. Then:
6x/(5x-63)=3/1
15x-189=6x
9x=189
x=21
6x=123 chickens were on the farm
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8 0

3 years ago

Read 2 more answers

For the following right triangle, find the side length x. Round your answer to the nearest hundredth.

Aleksandr-060686 [28]

Answer:

$\sqrt{113}$ = x

Step-by-step explanation:

In right triangles the sum of square length of two legs is equal to square length of hypotenuse:

7^2 + 8^2 = x^2

49 + 64 = x^2 add like terms

113 = x^2 find the root for both sides

$\sqrt{113}$ = x

8 0

2 years ago

Anyone know how to solve?

sergejj [24]

Answer:

was there more

Step-by-step explanation:

(i will edit answer)

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2 years ago

Find the coordinates of the point where the line <img src="https://tex.z-dn.net/?f=y%3D5x%2B7%5C%5C" id="TexFormula1" title="y=5

Anvisha [2.4K]

Answer:

(0, 7)

Step-by-step explanation:

The point that crosses the y-axis is called the y-intercept of the line.

We are given an equation of the line and we need to determine the y-intercept. This can be done by determining the constant in the equation.

What are constants?

Constants are such terms that include only numbers. There should be no variables in constants.

We know that:

$\bullet \ \text{Given equation of line: y = 5x + 7}$

The constant we can see in the equation is "7". Therefore, the y-intercept is 7.

Note: The y-intercept of the line must have an x-coordinate of 0.

Therefore,

⇒ Coordinates of y-intercept: (x, y) ==> (0, 7).

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2 years ago