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4 years ago

The difference of 3 times a number and 18 is 39. what is the number?

Mathematics

2 answers:

Setler79 [48]4 years ago

5 0

The number is 7(Seven).

Ber [7]4 years ago

4 0

Just set up an equation, with "x" being the unknown number.
3x-18=39
3x=57
x=19.
The unknown number is 19.

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Suppose the time that it takes a certain large bank to approve a home loan is Normally distributed with mean (in days) μ and sta

kolezko [41]

Answer:

Step-by-step explanation:

Null hypothesis (H0): population mean is equal to 5

Alternate hypothesis (Ha): population mean is greater than 5

Z = (sample mean - population mean) ÷ (sd/√n)

sample mean = 5.3, population mean = 5, sd = 1, n = 500

Z = (5.3 - 5) ÷ (1/√500) = 0.3 ÷ 0.045 = 6.67

Using the normal distribution table, for a one tailed test at 0.01 significance level, the critical value is 2.326

Conclusion:

Since 6.67 is greater than 2.326, reject the null hypothesis (H0)

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3 years ago

Jason built a rectangular tool shed that is 8 meters wide and has an area of 96 square meters. What is the length of Jason’s too

Tamiku [17]

96/8=12 so the answer is 12m

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3 years ago

Select all graphs that represent functions

mylen [45]

Answer:

where is the functions

Step-by-step explanation:

3 0

3 years ago

I don’t understand this assignment!!

Rashid [163]

Answer:

Equation of the Line: y = 1.25x + 5

Equation in Standard Form: 5x - 4y = -20

Step-by-step explanation:

y = mx + b

$\frac{17.5 - 22.5}{10 - 14}$ = $\frac{-5}{-4}$ = $\frac{5}{4}$ or 1.25

y = 1.25x + 5

Ax + By = C (A must be positive, and no fractions or decimals)

y = 1.25x + 5

-1.25x + y = 5

times -4

5x - 4y = -20

7 0

3 years ago

What is the equation of the quadratic graph with a focus of (3, 1) and a directrix of y = 5?

telo118 [61]

Answer:

$f(x)=-\frac{1}{8}(x-3)^2+3$

Step-by-step explanation:

We want to find the equation of the parabola with a focus of $(3,1)$ and directrix $y=5$ .

Considering the directrix, the quadratic graph must open downwards.

The equation of this parabola is given by the formula,

$(x-h)^2=4p(y-k)$ , where $(h,k)$ is the vertex of the parabola.

The axis of this parabola meets the directrix at $(3,5)$ .

Since the vertex is the midpoint of the focus and the point of intersection of the axis of the parabola and the directrix,

$h=\frac{3+3}{2}=3$ and $k=\frac{5+1}{2}=3$ .

The equation of the parabola now becomes,

$(x-3)^2=4p(y-3)$ .

Also $|p|$ is the distance between the vertex and the directrix.

$|p|=2$

This implies that $p=-2\:or\:2$ .

Since the parabola turns downwards,

$p=-2$ .

Our equation now becomes,

$(x-3)^2=4(-2)(y-3)$ .

$(x-3)^2=-8(y-3)$ .

We make y the subject to get,

$y=-\frac{1}{8}(x-3)^2+3)$ .

This is the same as

$f(x)=-\frac{1}{8}(x-3)^2+3)$ .

4 0

3 years ago