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3 years ago

Which of the following is a factor of x2 − 8x + 15?

Mathematics

2 answers:

IrinaVladis [17]3 years ago

5 0

Answer:

x+5

Step-by-step explanation:

edge

brilliants [131]3 years ago

3 0

Answer:

(x−3)(x−5)

Step-by-step explanation:

Let's factor x2−8x+15

x2−8x+15

The middle number is -8 and the last number is 15.

Factoring means we want something like

(x+_)(x+_)

Which numbers go in the blanks?

We need two numbers that...

Add together to get -8

Multiply together to get 15

Can you think of the two numbers?

Try -3 and -5:

-3+-5 = -8

-3*-5 = 15

Fill in the blanks in

(x+_)(x+_)

with -3 and -5 to get...

(x-3)(x-5)

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I need help I don't understand this

Naddik [55]

Answer:

x = 2

Step-by-step explanation:

-3 +6x = 25 -8x

Add 8x to each side

-3 +6x+8x = 25 -8x=8x

-3+14x = 25

Add 3 to each side

-3+3+14x = 25+3

14x = 28

Divide by 14

14x/14 = 28/14

x = 2

8 0

3 years ago

Read 2 more answers

a construction company needs to remove 24 tons of dirt from a construction site. They can remove 3/8 tons of dirt each hour. How

Sunny_sXe [5.5K]

Since each hour is 3/8 of a tone then, namely how many times does 3/8 go into 24? well, is just their quotient.

$\bf 24\div\cfrac{3}{8}\implies \cfrac{24}{1}\div\cfrac{3}{8}\implies \cfrac{24}{1}\cdot\cfrac{8}{3}\implies \cfrac{8}{1}\cdot \cfrac{8}{1}\implies 64$

4 0

3 years ago

I don't understand what I have to do. HELP

Volgvan

Basically what you are doing is trying to find the square root of 8. What you need to do is find what would go into the number 8 equally so, you are basically finding the multiples

8 0

3 years ago

Suppose that y varies directly with x and y=10 when x=20. What is y when x=15

Likurg_2 [28]

Answer:

y=kx

subst y=10 and x=20 into the above

10=k20

k=10/20

k=1/2

therefore relationship: y=1/2x

subst x=15 into the relationship

y=1/2(15)

y=7,5

Step by step explanation:

Step 1: when they say y varies directly with x they mean y is proportional to x
step 2: so y=kx where k is the constant
step 3: is to substitute y=10 and x=20 into the above equation y=kx
step 4: you will end up with 10=k20 then divide both sides by 20 so that k becomes the subject of the formula 
step 5: your answer from the above will be k=10/20 so the relationship is y is directly proportional to 1/2 x what you did here is that you substituted k for 1/2 in the equation in step 3
step 6: is to finally substitute x=15 into the equation y=1/2x to finally get your answer y=7,5.

4 0

3 years ago

Bobby wants to go on a school trip that will cost him $250. He comes up with an equation that represents how much he needs to sa

monitta

Yes, Bobby will have enough money if he saves for 9 weeks. You can find this through either substituting w for 9 in the equation, or solving the equation itself.

Substituting:

$25(9)+30$
Substitute w for 9.

$225+30$
Simplify.

$225+30=255$
Solve.

255 is greater than 250, so yes, he will have enough money saved.

Solving the equation:

$25w+30=250$
Original Equation

$25w=220$
Subtract 30 from both sides.

$w=8.8$
Divide both sides by 25.

The number of weeks he needs is 8.8. When rounding it up, you get 9.

4 0

3 years ago