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4 years ago

If f(x) = x2 – 3x – 40 intersects the x-axis at points A and B, what is the sum of A and B?

Mathematics

1 answer:

Eduardwww [97]4 years ago

4 0

Answer:

Step-by-step explanation:

Intersections on the x axis occur when y = 0. f(x) is another term for y, so set f(x) equal to zero and solve for the two possible x's.

0 = x^2 - 3x - 40

0 = (x-8)(x+5)

By solving for x, you get 8 and -5. 8 and -5 added together will equal 3.

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Calculate the perimeter of the regular hexagon which has 8 sides Pls help I’m stuck

snow_lady [41]

6+6+6+6+6+6+6+6= 48

The perimeter is 48.

6 0

3 years ago

Ellen saved $2000 and she spent 10% of it to buy a bike. Kim saved 8% more than that of Ellen's left savings. If Lisa saved 60%

enyata [817]

Answer: Lis saved $1166.4 .

Step-by-step explanation:

Given , Ellen saved $2000 and she spent 10% of it to buy a bike.

Then, Ellen's left saving = saved amount - 10% of (saved amount)

= $2000 - 0.10 x $2000 [We convert perecntage to decimal by diving it by 100]

= $2000 - $200

= $1800

So, Ellen's left saving= $1800

Also, Kim saved 8% more than that of Ellen's left savings.

Kim's Saving = Ellen's left saving + 8% of (Ellen's left saving)

= $1800 + (0.08) x ($1800) [We convert perecntage to decimal by diving it by 100]

= $1800 + $144

i.e. Kim's Saving= $1944

If Lisa saved 60% as much as Kim, then Lisa's saving = 60% of (Kim's Saving)

= (0.60) x ($1944) [We convert perecntage to decimal by diving it by 100]

i.e. Lisa's saving = $1166.4

4 0

3 years ago

A survey was given asking whether people like dogs and/or cats. 153 said they like dogs 191 said they like cats 56 said they lik

lapo4ka [179]

Answer:

There were 362 people surveyed

Step-by-step explanation:

* Lets explain how to solve the problem

- A survey was given asking whether people like dogs and/or cats

# 153 said they like dogs

# 191 said they like cats

# 56 said they liked both cats and dogs

# 74 said they don't like cats or dogs

- We need to find how many people were surveyed

* Lets find the number of who likes dogs only and the number who

likes cats only

- The number who likes dog only (cats only) is the difference between

the number who likes dogs (cats) and the number who likes both

∴ The number who likes dogs only = 153 - 56 = 97

∴ The number who likes cats only = 191 - 56 = 135

- The total number of people were surveyed is the sum of the number

who likes cats only and who likes dogs only and who likes both and

who doesn't like both

∵ The number who doesn't like dogs or cats is 74

∴ The total number = 97 + 135 + 56 + 74 = 362

* There were 362 people surveyed

7 0

3 years ago

Don’t undersatnd please help

Ludmilka [50]

The inequality of this question would be 4

3 0

3 years ago

I need help with this problem:(

steposvetlana [31]

Answer:

Step-by-step explanation:

According to Euclidean theorem

m^2 = 4×16

m^2 = 64

m = 8

3 0

3 years ago