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4 years ago

Can someone explain 5. please ?

Mathematics

1 answer:

GuDViN [60]4 years ago

5 0

Both denominators are 4, so we can add the numerators to place over the common denominator. The numerators are -3 and -3, which add to -6. One way to think of negative numbers is to think of IOUs, which are a way of expressing debt in money. For instance, if you go into a store and buy a $10 item, but only have $3 in your pocket, then you would have to owe the owner $7. This can be represented with -7. If you repeat the process, then you'd have 7+7 = 14 in IOUs total. This would be represented with -14

In short, adding negative numbers is really the same as adding positives, but the final result is negative

So that's why -3+-3 turns into -6. We add the two threes like normal but then make the final result negative. All throughout this process, the denominator stays at 4.

So we end up with -6 over 4 which reduces to -3 over 2. How is this reduction happening? We are simply dividing each piece by the greatest common factor 2.

-6 divided by 2 = -3

4 divided by 2 = 2

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1/2(12k-6) plzzz help i suck at 7th grde math

Rufina [12.5K]

6k-3 is the simplified form
Hope this helps

6 0

3 years ago

Read 2 more answers

The volume of a cone varies jointly as the height of the cone and the area of the base. The volume of a cone with height 30 cent

irina [24]

Answer:

V₂=28cm³

Step-by-step explanation:

Way 1

The volume of a cone is $V=\frac{\pi r^{2}h}{3}$ , and h₁ = 30 cm but the base (Ba₁) is 14 cm², so

$V=\frac{Ba.h}{3}$ , where Ba= Base area

if h₂=7cm and Ba₂=12cm² then

$V_{1} =\frac{12cm^{2}.7cm}{3}=28cm^{3}$

Way2

If the volume of a cone varies jointly as the height of the cone and the area of the base, then we must find the relationship between the bases and heights of the cones

Ba₁*h₁ = 30cm*14cm² = 420cm³

Ba²*h²= 7cm*12cm² = 84cm³

420/84 = 5; ratio = 5 also

V₂=V₁/5 ⇒ V₂=140cm³/5 = 28cm³

8 0

3 years ago

Read 2 more answers

I need ur smart brain power!!!!!

Andrej [43]

Answer:

y = -2x -3

Step-by-step explanation:

I love slope-intercept form! lol

y =mx +b

so we have 2 points given: (-1,5) and (4,-5)

to find the SLOPE of the slope-intercept form, we need to subtract and divide

(-5-5)/(4+1)

-10/5= -2 which is our slope

now! lets translate this info into point slope form. y - y1 = m (x - x1)

(-1,5) and we kno the slope is -2.

y - 5 = -2 (x - (-1))

y-5 = -2(x + 1)

y-5 = -2x -2

add five

y = -2x -3 we are back to slope intercept form! YAY!

3 0

3 years ago

If 36 is 30%, what is 100%

Sophie [7]

36 30%
____ = _____
x 100%

Cross multiply and divide
x=120

6 0

3 years ago

Giving 100 points.

Nitella [24]

Answer:

1. Cost per customer: 10 + x

Average number of customers: 16 - 2x

$\textsf{2.} \quad -2x^2-4x+160\geq 130$

3. $10, $11, $12 and $13

Step-by-step explanation:

Given information:

$10 = cost of buffet per customer
16 customers choose the buffet per hour
Every $1 increase in the cost of the buffet = loss of 2 customers per hour
$130 = minimum revenue needed per hour

Let x = the number of $1 increases in the cost of the buffet

Part 1

Cost per customer: 10 + x

Average number of customers: 16 - 2x

Part 2

The cost per customer multiplied by the number of customers needs to be at least $130. Therefore, we can use the expressions found in part 1 to write the inequality:

$(10 + x)(16 - 2x)\geq 130$

$\implies 160-20x+16x-2x^2\geq 130$

$\implies -2x^2-4x+160\geq 130$

Part 3

To determine the possible buffet prices that Noah could charge and still maintain the restaurant owner's revenue requirements, solve the inequality:

$\implies -2x^2-4x+160\geq 130$

$\implies -2x^2-4x+30\geq 0$

$\implies -2(x^2+2x-15)\geq 0$

$\implies x^2+2x-15\leq 0$

$\implies (x-3)(x+5)\leq 0$

Find the roots by equating to zero:

$\implies (x-3)(x+5)=0$

$x-3=0 \implies x=3$

$x+5=0 \implies x=-5$

Therefore, the roots are x = 3 and x = -5.

Test the roots by choosing a value between the roots and substituting it into the original inequality:

$\textsf{At }x=2: \quad -2(2)^2-4(2)+160=144$

As 144 ≥ 130, the solution to the inequality is between the roots:

-5 ≤ x ≤ 3

To find the range of possible buffet prices Noah could charge and still maintain a minimum revenue of $130, substitute x = 0 and x = 3 into the expression for "cost per customer.

[Please note that we cannot use the negative values of the possible values of x since the question only tells us information about the change in average customers per hour considering an increase in cost. It does not confirm that if the cost is reduced (less than $10) the number of customers increases per hour.]

Cost per customer:

$x =0 \implies 10 + 0=\$10$

$x=3 \implies 10+3=\$13$

Therefore, the possible buffet prices Noah could charge are:

$10, $11, $12 and $13.

8 0

2 years ago