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
lukranit [14]
3 years ago
15

Multiply each polynomial (x + 5)(x+4) teach me step by step

Mathematics
1 answer:
lara [203]3 years ago
6 0

Answer: x^2 + 9x + 20

Step-by-step explanation:

Foil Method: (a + b) (c + d) = ac + ad + bc + bd

Lets say:

a = x

b = 5

c = x

d = 4

Plugging in the numbers: xx + 4x + 5x + 5*4

Combine like terms:

xx = x^2

4x + 5x = 9x

5 * 4 = 20

You're then left with: x^2 + 9x + 20

You might be interested in
Please explain with working!!! Find the set of values of x that satisfy the inequality 9x^2-15x<6
Oksi-84 [34.3K]

Answer:

-1/3

Step-by-step explanation:

When solving a quadratic inequality, first solve it normally like you would for a normal quadratic equation. We have:

9x^2-15x

Ignore the less than sign and replace it with an equal sign and solve the quadratic for its zeros:

9x^2-15x=6

Subtract 6 from both sides:

9x^2-15x-6=0

Divide everything by 3:

3x^2-5x-2=0

Factor. Find two numbers that equal (3)(-2)=-6 that add up to -5.

-6 and 1 works. Thus:

3x^2-6x+x-2=0\\3x(x-2)+1(x-2)=0\\(3x+1)(x-2)=0

Find the x using the Zero Product Property:

3x+1=0 \text{ or }x-2=0\\x=-1/3\text{ or }x=2

Now, we need to replace the equal signs with symbols again. To do so, we need to test which symbol to place. Let's do the first zero first.

So, the first zero is:

x=-1/3

Assume that the correct symbol is >. Thus,

x>-1/3

Now, pick any number that is greater than -1/3. I'll pick 0 since it's the easiest. Now, plug 0 back into the very original inequality. If it works, then the sign is correct, if it doesn't, then simply use the opposite one. Therefore:

9x^2-15x

0 is indeed less than six, so our first correct solution is:

x>-1/3

For the second one, do the same thing. We have:

x=2

Assume that the correct symbol is <. Thus:

x

Again, pick any number less than 2. I'm going to use 0. Plug 0 back into the original equation

9x^2-15x

Again, this is correct. Therefore, x<2 is also the correct inequality.

So together, we have:

x>-1/3 \text{ and } x

Together, we can write them as:

-1/3

(Note that we don't need to worry about the "or equal to" part since the original inequality didn't have it.)

6 0
3 years ago
Can someone give me the answers for theses I’ve been lost all day with online school
lilavasa [31]

Answer:

True. That is a function.

Step-by-step explanation:

A function just means that every input has only one output. The simpler way to do these is the vertical line test. Draw a vertical line anywhere on the graph and see if the vertical line is intersected in two places. If the vertical line is crossed twice, the graph isn't a function.

6 0
3 years ago
GEOMETRY!! Will give brainliest
svetoff [14.1K]

Answer:

60

Step-by-step explanation:

(20x15)0.5

6 0
3 years ago
Read 2 more answers
Which functions have a horizontal asymptote? Y = f(x) y = h(x) y = g(x) y = k(x) On a coordinate plane, 4 exponential functions
Fed [463]

Answer:

Is all of them !!

Step-by-step explanation:

Because they all have asymptote

5 0
3 years ago
Read 2 more answers
Divide nine by three then subtract two double the results
IrinaVladis [17]

Answer:

2

Step-by-step explanation:

8 0
3 years ago
Read 2 more answers
Other questions:
  • Which of the following inequalities is false?
    8·1 answer
  • Simplify the expression 7 x 3g
    14·2 answers
  • Which of the following functions is graphed below?
    7·1 answer
  • In your own words, how geometric seqences are related to exponetiol functions
    5·1 answer
  • Please help I am very confused. I would really appreciate it if someone helped me. Thank you!
    7·2 answers
  • What is the range of the following set of numbers 22,44,66,88
    6·2 answers
  • How many times do 5 go into 8
    15·2 answers
  • Miles picked 12 bushels of vegetables in 3 hours. Working at the same rate, how many bushels
    7·1 answer
  • Find the linear function for f(1) = 3 and f(4) = 0
    8·1 answer
  • the length of the rectangle is measured as 370mm correct to 2 significant figures.a) what is the upper bound for the length?the
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!