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3 years ago

X = 10 5x − 4y = 18 substetution need fast

1 answer:

4 0

Y = 8

Explanation:

X = 10

5x - 4y = 18

5(10) - 4y = 18

50 - 4y = 18

50 - 4y = 18
-50 -50

-4y = -32

-4y/-4 = -32/-4

y = 8

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What is the y-intercept of the function f(x)=4 - 5x? (Hint: use the commutative property)

Tom [10]

Answer:

Therefore the y-intercept of the function is 4.

Step-by-step explanation:

Intercepts:

The line which intersect on x-axis and y-axis are called intercepts.

y-intercept: The line or function which intersect at y-axis. So when the line intersect at y-axis, X coordinate is zero.

So in the given Function Put x = 0 we will get the y-intercept

$f(x)= 4-5x$

Put x =0

$f(0)= 4-5\times 0$

$f(0)= 4-0=4$

Therefore the y-intercept of the function is 4.

7 0

3 years ago

The lead statue of the Korean War Memorial in Washington DC casts a 43.5 inch shadow at the same time a nearby tourist casts a 3

AfilCa [17]

Answer:

The lead statue is 87 inches tall

Step-by-step explanation:

Let

x ----> the height of the lead statue

using proportion

we know that

The height of the lead statue divided by the length of his shadow must be equal to the height of the tourist divided by the length of his shadow.

$\frac{x}{43.5}=\frac{64}{32}\\\\\frac{x}{43.5}=2\\\\x=2(43.5)\\\\x=87\ in$

3 0

3 years ago

Leonardo makes the following purchases at the store: 1 backpack for $16.89 5 spiral notebooks for $1.19 each 1 pack of mechanica

solong [7]

I believe the correct answer is he paid the right amount

3 0

3 years ago

Read 2 more answers

What is the product?

Leya [2.2K]

Answer:

5/4k^2

Step-by-step explanation:

P=5\dfrac{k}{6}\times \dfrac{3}{2k^3}.

We will be using the following property of exponents:

\dfrac{a^x}{a^y}=a^{x-y}.

We have

P\\\\\\=5\dfrac{k}{6}\times\dfrac{3}{2k^3}\\\\\\=\dfrac{5}{6}\times\dfrac{3}{2}k^{1-3}\\\\\\=\dfrac{5}{4}k^{-2}=\dfrac{5}{4k^2}.

Thus, the required product is \dfrac{5}{4k^2}.

Read more on Brainly.com - brainly.com/question/8858421#readmore

8 0

3 years ago

Read 2 more answers

An educational psychologist wishes to know the mean number of words a third grader can read per minute.

Rama09 [41]

Answer: 208.

Step-by-step explanation:

The formula to find the minimum sample size is given by :-

$n= (\dfrac{z^*\times \sigma}{E})^2$ (1)

, where z* = critical z-value (two tailed).

$\sigma$ = Standard deviation ( from prior study ) and E = Margin of error.

As per given , we have

Margin of error : E= 0.29

Confidence level = 85%

Significance level = $\alpha=1-0.85=0.15$

Using z-table , the critical value (two -tailed)= $z^*=z_{\alpha/2}=z_{0.15/2}=z_{0.075}=1.439$

As per previous study , Variance = $\sigma^2=8.41$

$\sigma=\sqrt{8.41}=2.9$

Now, the required minimum sample size = $n= (\dfrac{(1.439)\times (2.9)}{0.29})^2$ [Substitute the values in formula (1)]

$n=(14.39)^2$

$n=207.0721\approx208$ [ Round to the next integer]

Hence, the minimum number of third graders that must be included in a sample = 208.

5 0

3 years ago