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
ivann1987 [24]
4 years ago
5

How do you work out this problem using completing the square x2 - 4x - 80 = 0

Mathematics
2 answers:
Ugo [173]4 years ago
7 0

x^2 - 4x = 80

x^2 - 4x + 4 = 80 + 4 (Divide b, which is 4, by 2 and square it.)

x^2 - 4x + 4 = 84

sqrt(x + 2)^2 = sqrt(84)

x + 2 = plus or minus sqrt(84)

Subtract 2 from both sides

x = -2 plus or minus sqrt(84)

yulyashka [42]4 years ago
3 0

Answer:

A value that satisfies this equation is called a root, zero or solution of the equation!! We have three ... Solve each by factoring. 1) x2 + 4x -5 = 0 ... Follow the explanation and sample problem to review completing the square.

Step-by-step explanation:

You might be interested in
If an equation of the tangent line to the curve y=f(x) at the point where a = 2 is y=4x-5 find f(2) and f'(2)
vichka [17]
 hello : 
at the point where a=2   y = 4(2)-5 =3 (commun the curve and the tangent)
so :f(2) = 3
f'(2) =4 (slope of the tangent )
5 0
3 years ago
Write a<br> rule that could be used to simplify the square of any square root of a number.
Vlada [557]
Product rule- the first rule for simplifying square roots, which allows us to separate the square root of a product of two numbers into the product of two separate rational expressions


HOPES THIS HELP :)
5 0
3 years ago
the cost to buy a sweater at sweaterfactory.com is 19 with free shipping i have 50 dollars creat an inequality to represent how
pychu [463]

Answer:

34

Step-by-step explanation:

5 0
3 years ago
The radius of the base of a cylinder is 27 cm and its height is 37 cm. Find the surface area of the cylinder in terms of π
Nonamiya [84]
Surface area of a cylinder = 2 x Pi x r^2 + 2 x Pi x r x h

R = 27 cm
H = 37 cm

Take away the Pi seeing as you want to keep it in terms of Pi

2 x 27^2 + 2 x 27 x 37 = 3456 Pi cm^2
Your answer is B
7 0
3 years ago
Read 2 more answers
Which residual plots indicate that the original data set has a linear relationship? Check all that apply
VMariaS [17]

Answer: A, B and E

Step-by-step explanation:

A residual values should be equally and randomly spaced around the horizontal axis. If the plot looks like any of the images in C and D, then the data set is probably not a good fit for regression. A non-linear pattern is more appropriate.

3 0
3 years ago
Other questions:
  • May I also get help on this
    14·2 answers
  • Math in the real world
    12·2 answers
  • Given: Q=7m + 3n, R= 11 - 2m, S= n + 5, and T= -m - 3n + 8 <br><br><br> simplify R - [S + T]
    12·2 answers
  • NEED HELP ASAP PLEASE How many 3-digit numbers with all odd digits exist
    15·2 answers
  • Kay earns $78,400 per year. She takes a standard deduction of $5,700 and pays tax at a 21% rate. What is the amount of Kay's inc
    7·1 answer
  • What is the exact value of tan 75 degrees
    14·1 answer
  • PLEASE PLEASE HELP!! This is overdue
    14·1 answer
  • Describe the shape below.
    11·2 answers
  • A group of friends chartered a deep-sea fishing boat out of destin, fl. the graph below represents the total cost, in dollars, o
    7·1 answer
  • /13 Quiz High School Math Focus Practice ItemsQuestion 2 of 15Question 2 (1 point)Consider this right triangle. Enter the measur
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!