1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Morgarella [4.7K]
3 years ago
15

Solve the equation by completing the square. x^2 -2x = 15

Mathematics
1 answer:
dlinn [17]3 years ago
5 0

Answer:

x = -3  or  x = 5

Step-by-step explanation:

Solve:   x^2 -2x = 15

x^2  - 2x  - 15 = 0

Use the Diamond method of factoring

-15 = 3* -5  and  3 - 5 = -2  so...

x^2  - 2x  - 15 = x^2 -  5x  + 3x  -  15

x^2  - 2x  - 15 = x *(x - 5)  + 3*(x - 5)

x^2  - 2x  - 15 = (x  + 3)*(x - 5)

x^2  - 2x  - 15 = (x  + 3)*(x - 5)  = 0

solve  (x + 3 ) = 0  and  (x - 5) = 0

x = -3  or  x = 5

You might be interested in
Step 6: Patterns can provide a clear understanding of mathematical relationships. This can be seen very clearly in the form of m
kenny6666 [7]

Two more examples of relationship patterns found in mathematics are <u>Geometric sequences</u><u> and </u><u>Fibonacci numbers</u>.

<h3>What are mathematical patterns?</h3>

Mathematical patterns are a sequence of repeated arrangements of numbers, shapes, colors, letters, etc.

Mathematical patterns are usually abstract.

<h3>What is a geometric sequence?</h3>

A geometric sequence is a sequence of non-zero numbers.  The first number is the product of multiplying a previous number by a fixed, non-zero number, called the common ratio.

A Geometric sequence may look like: 2, 4, 8, 16, 32, 64, 128, ..., where the common ratio is 2.

<h3>What is a Fibonacci sequence?</h3>

A Fibonacci number starts with a zero, followed by a one, then by another one, and then by a series of steadily increasing numbers.

The rule of the Fibonacci sequence is that each number is equal to the sum of the preceding two numbers, for example, 0, 1, 1, 2, 3, 5, 8, 13.

Learn more about mathematical patterns at brainly.com/question/854376

#SPJ1

5 0
2 years ago
A man is standing at a radar base and observes an unidentified plane at an altitude 6000m flying towards the radar base at an an
liubo4ka [24]

Answer:

The speed in of the plane is 115.47 m/sec

Step-by-step explanation:

Given:

Height at which the plane is flying = 6000 m

Angle of elevation at the radar base = 30 Degrees

Angle of elevation at the radar base after one minute  = 60 Degrees

To Find:

The Speed of the plane in meter per second = ?

Solution:

Let us use the tangent of the angle to find the distance (d) to a point directly below plane:

<u>when the angle is 30 degrees</u>

tan(30) = \frac{6000}{d1}

d1   = \frac{6000}{tan(30)}

d1 = \frac{6000}{0.577}

d1 = 10392.3 meters

<u>when the angle is 60 degrees</u>

tan(60) = \frac{6000}{d2}

d2  = \frac{6000}{tan(60)}

d2  = \frac{6000}{1.732}\\

d2 = 3464.1 meters

<u>distance travelled by aircraft in 1 min is  </u>

=>d1 - d2

=>0392.3 - 3464.1

= 6928.2 m/min

<u>Now converting to m/sec</u>

=>\frac{6928.2}{60}

=>115.47 m/sec

4 0
3 years ago
Please help with geometry homework !!!
Umnica [9.8K]

You can solve this with next proportion =>

3 : 5 = 4 : x => 3x= 5*4 => 3x = 20 => x=20/3 = 6 (2/3)

The correct answer is  x= 6 (2/3)

Good luck!!!

5 0
3 years ago
Darnell is trying to understand the Pythagorean Theorem by drawing a few triangles. He found that 1² + 1² = (√2)² is accurate. W
Sergeeva-Olga [200]

Answer:

D. The triangle is a right triangle, the lengths of its sides are 1 and 1 with a hypotenuse of √2.

Step-by-step explanation:

The Pythagorean Theorem is modeled by a² + b² = c².

c represents the hypotenuse and a and b represent the other two sides.

The Pythagorean Theorem can only be applied to right triangles.

7 0
2 years ago
Read 2 more answers
There are 18 female students and 16 male students in a class. Which of the following expresses the ratio of female students to m
Alex Ar [27]
9:8 
 9 female to 8 male
6 0
3 years ago
Read 2 more answers
Other questions:
  • Cavalieri’s principle states that two solids with equal heights and cross sectional volumes at every level have equal areas
    12·2 answers
  • Intr-o clasa snt 35 de elevi .nr fete este egal cu 75 la suta din nr baietilor .aflati nr baietilor
    11·1 answer
  • Of 30 students 1/3 play sports of those students 2/5 play soccer, how many students play soccer
    10·2 answers
  • A total distance greater than 10 kilometers and less than or equal to 30 kilometers
    12·2 answers
  • Help fast please!!! <br> Find the values of x and y.
    9·2 answers
  • Please help solve this math problem
    15·1 answer
  • Saj has made 7 litres of curry sauce.
    13·1 answer
  • Can someone help me? Plss
    14·1 answer
  • Find the coordinates of the midpoint of ST with endpoints S(−2, −1) and T(1, −4)
    6·1 answer
  • Find the sale price when the original price is $91.00 and the discount rate is 13%
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!