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2 years ago

Factorise and solve x^2 + 4x -21 = 0

Mathematics

2 answers:

Korvikt [17]2 years ago

3 0

Answer:

(x + 7) (x - 3)

Step-by-step explanation:

Find 2 numbers that add to 4 and multiply to -21

(x + 7) (x - 3)

Ahat [919]2 years ago

3 0

Answer:

(x+7)(x-4) x=-7,4

Step-by-step explanation:

The factors of -21 that add up to 4 are 7 and -3, so put those as your two second values in your binomials and solve for x, in this case being the negative versions of the second term in the binomial

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A 50 loot ladder is leaning against a building. If the base of the ladder is 35 feet from the base of the building, how far up t

Hatshy [7]

Answer:

The ladder is 35.71 feet up the building

Step-by-step explanation:

Here, we want to calculate how far up the building is the ladder placed

We should picture a right angled triangle with hypotenuse 50 and one of the other sides as 35

To find the height in this case, we proceed to use Pythagoras’ theorem which states that the square of the hypotenuse equals the sum of the squares of the two other sides

In this case, let the height be

50^2 = 35^2 + h^2

h^2 = 50^2-35^2

h^2 = (50+35)(50-35)

h^2 = (85)(15)

h^2 = 1275

h = square root of 1275

h = 35.71 ft

3 0

2 years ago

The double number line shows that in 222 minutes, Pogo the dog can fetch a frisbee 666 times. Based on the ratio shown in the do

Ilia_Sergeevich [38]

Answer:

Dog Pogo will fetch the frisbee <u>12 times</u> in 4 minutes.

Step-by-step explanation:

Given:

Number of minutes required =2 minutes.

Number of times frisbee fetch by dog = 6 times

We need to find Number of times the dog can fetch the frisbee in 4 minutes.

First we will find number of frisbee fetch in minute.

In 2 minutes = 6 times frisbee fetched by the dog

so in 1 minute = Number of times frisbee fetched by the dog in 1 minute.

By using Using Unitary method we get;

Number of times frisbee fetched by the dog in 1 minute = $\frac{6}{2} =3$

Hence in 1 minutes the dog can fetch frisbee 3 times.

for 1 min = 3 times frisbee is been fetched by dog

So for 4 minutes = Number of times frisbee is been fetched by dog in 4 min.

Again by using Unitary Method we get;

Number of times frisbee is been fetched by dog in 4 min = $3\times4 = 12$

Hence Dog Pogo will fetch the frisbee <u>12 times</u> in 4 minutes.

8 0

2 years ago

Read 2 more answers

Please solve <img src="https://tex.z-dn.net/?f=18%5E2%5Ex%5E-%5E1%3D100" id="TexFormula1" title="18^2^x^-^1=100" alt="18^2^x^-^1

mel-nik [20]

Answer: x= log18 (10) +1/2
x= 1.29664

Good luck !

8 0

2 years ago

A triangle ABC is reflected across the y-axis and then translated 5 units down to triangle A'B'C'. How are the side lengths of t

Oksi-84 [34.3K]

Answer:

d, c, a, b

d= 32, 56

c = 34, 64

a = 85, 92

b = 23, 55

Step-by-step explanation:

3 0

2 years ago

Bank A charges a monthly service fee of $5.00 and a per-check fee of $0.05,

Anna007 [38]

Answer:

2 + .05x = 1.5 +.1x

.5 = .05x

x =10 is number when costs are equal

So the 11th check makes Bank A cheaper

Step-by-step explanation:

3 0

2 years ago