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
liubo4ka [24]
3 years ago
8

Solve x2 - 4x - 7 = 0 by completing the square. What are the solutions?

Mathematics
1 answer:
Roman55 [17]3 years ago
5 0

Answer:

x= 2 + √11 or x = 2 −√11

Step-by-step explanation:

I am going to complete the square step-by-step.

x² − 4x − 7=0

Step 1: Add 7 to both sides.

x² − 4x − 7+ 7 = 0 + 7

x² − 4x = 7

Step 2: The coefficient of -4x is -4. Let b = -4.

Then we need to add (b/2)² = 4 to both sides to complete the square.

Add 4 to both sides.

x² − 4x + 4 = 7 + 4

x² − 4x + 4 = 11

Step 3: Factor left side.

(x−2)² = 11

Step 4: Take square root.

x − 2 = ±√11

Step 5: Add 2 to both sides.

x − 2 + 2 = 2 ±√11

x = 2 ±√11

x= 2 + √11 or x = 2 −√11

You might be interested in
Which of the following numbers is irrational?
erma4kov [3.2K]
-7.8

The rest can be solved as rational. Negative numbers are not rational.

6 0
3 years ago
Read 2 more answers
Factor each trinomial. Then match the polynomial (term) on the left with its factored form (definition) on the right.
Salsk061 [2.6K]
<span>x2 – 4x – 12 A) (x – 6)(x + 2) x2 + 4x – 12 B) Prime x2 – x – 12 C) (x – 4)(x + 3) x2 – 7x – 12 D) (x – 2)(x + 6) i think this is the awnser:)</span>
7 0
3 years ago
Read 2 more answers
What are the solutions to the equation? x^3 - 8x^2 - x + 8 =0
kogti [31]

Answer:

Step-by-step explanation:

x^3 - 8x² - x + 8 =0

x^3 - 8x² - (x - 8 )=0

x²(x-8) - (x-8) = 0

(x-8)(x² -1) =0

x-8 = 0  or x² - 1 = 0

x-8=0 or (x-1)(x+1)=0

x=8 x=1 or x=-1

8 0
3 years ago
Read 2 more answers
4. (03.03 HC)
Kitty [74]

Answer:

A. yes, the data represents a function because u have no repeating x values. A function cannot have repeating x values...they can have repeating y values, just not the x ones

Step-by-step explanation:

B. table : (8,8)(12,12)(14,16)(16,16)

               look at ur points...when x = 8, y = 8...so the table, when x = 8 has a

               value of 8

relation : f(x) = 8x - 5....when x = 8

             f(8) = 8(8) - 5

             f(8) = 64 - 5

             f(8) = 59....and the relation has a value of 59

Therefore, the relation has a greater value when x = 8 <==

C. f(x) = 8x - 5...when f(x) = 19

    19 = 8x - 5

     19 + 5 = 8x

    24 = 8x

    24/8 = x

    3 = x <==

7 0
3 years ago
What is the value of the expression |-7+ |-4/?
KonstantinChe [14]

Answer:

11

Step-by-step explanation:

8 0
3 years ago
Other questions:
  • Suppose $10000 is deposited in a bank at 3.5% annual interest. what is the interest earned after one year
    14·1 answer
  • You have 120 pieces of fabric to make a blanket. Each piece is a square with a side length of 6 inches. You can use as many piec
    9·1 answer
  • Earned income and capital gains (or portfolio income) are acquired in different ways. Which statement describes how they are dif
    10·2 answers
  • If x-2y=0 and 3x + y =7 what is the value of x
    10·1 answer
  • Would it ever be possible for the temperature in Celsius ( Value in numbers) to have a greater value than the temperature in Fah
    6·1 answer
  • Out or 1,000,000,000.00, how many 10,000.00s are there?
    6·1 answer
  • How to solve similar integer
    10·1 answer
  • 21.18 - 17.92 rounded to the nearest whole number
    6·1 answer
  • G (r)=-5r+13<br> g(3) Evaluate Functions
    9·1 answer
  • Can somebody help me with this please
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!