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3 years ago

Y varies directly with x, and y = 5 when x = 4. What is the value of x when y = 8?

1 answer:

7 0

As y varies directly with x, there is a proportionality constant. As x increases by that certain constant, y also increases. We equate:
y = kx
where k = proportionality constant.
Given the condition, y = 5 when x = 4, then we solve for k:
5 = k(4)
k = 5/4 or 1.25
When y = 8, then
8 = (5/4)(x)
x = 8/(5/4) = (8)(4/5) = 32/5 or 6.4 (ANSWER)

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A triangle has an area of 900m2 . If a parallelogram has the same height and base as the triangle, what is the area of the paral

timama [110]

Answer:

1800 $m^{2}$ is the area of parallelogram.

Step-by-step explanation:

Given that:

Area of a triangle = 900 $m^{2}$

To find:

Area of a parallelogram which has same height and base as that of the given triangle.

Solution:

First of all, let us have a look at the formula for Area of a parallelogram:

$Area_{Par} = Base \times Height$ ...... (1)

So as to find the area of a parallelogram, we need to have the product of Base and Height of Parallelogram.

Now, let us have a look at the formula for area of a triangle:

$Area_{Tri} = \dfrac{1}{2} \times Base \times Height$

Given that height and base of triangle and parallelogram are equal to each other.

So,the product of base and height will also be equal to each other.

$900 = \dfrac{1}{2} \times Base \times Height\\\Rightarrow Base \times Height = 2 \times 900\\\Rightarrow Base \times Height = 1800\ m^2$

By equation (1):

Area of parallelogram = 1800 $m^{2}$

4 0

2 years ago

What is the value of x? 3x−8=8x+4/2 Enter your answer in the box.

bekas [8.4K]

Answer:

x = -2

Step-by-step explanation:

3x -8 =8x +4/2

3x -8 =8x +2

3x -3x -8 = 8x -3x +2 (subtract 3x both sides )

-8 = 5x +2

-8-2 =5x+2 -2 (subtract 2 both sides )

-10 =5x

-10/5 = 5x/5 (divide 5 both sides)

-2 = x

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2 years ago

A pair of shoes cost $40 is marked up by 25%. What is the RETAIL PRICE?

Nitella [24]

The retail price is $50 because 25% of 40 is 10 and 10+40=50.

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3 years ago

How much is f(x) = 3(4)x

a_sh-v [17]

Answer:

f ( x ) = 12 x

Step-by-step explanation: 3x4=12 so that makes it f(x)=12x

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2 years ago

Sandra used partial products to find the product of 438 × 17 by multiplying 438 by 1 and 438 by 7 to get 3,066. Find the product

boyakko [2]

Let us determine the product of 438 and 17 by partial products.

Consider $438 = 400+30+8$

and $17 = 10+7$

So, $438 \times 17 = (400+30+8) \times (10+7)$

$438 \times 17 = (400\times 10)+(30 \times 10)+(8 \times 10) +(400 \times 7)+(30 \times 7)+(8 \times 7)$

= $438 \times 17 = (4000+300+80+2800+210+56)$

= 7446

Therefore, the product of 438 and 17 is 7446.

No, Sandra's answer is not correct.

Because she should have expressed 17 as (10+7), then if she multiplied (438 by 10) and (438 by 7). And, then added the results.Then her answer would be correct.

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2 years ago