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3 years ago

A rectangle has length (x-3) cm and width 4 cm. The perimeter of the rectangle is 40 cm. Find the length.

Mathematics

2 answers:

Marina86 [1]3 years ago

7 0

2(x-3)+2(4)=40
2x-6+8=40
2x+2=40
2x=38
x=19
Length=(x-3)=(19-3)=16 cm

Sav [38]3 years ago

5 0

We actually don't need to solve for x, just legnth

P=2(L+W)
40=P
L=x-3=L (since we are solving for Legnth not specifically x)
W=4

40=2(L+4)
divide both sides by 2
20=L+4
minus 4 both sides
16=L

legnth=16 cm (x=19 just fyi)

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16 is divided by the sum of a number q and 1. The result is 4. What is the number?

GaryK [48]

16/(q+1)=4
16/(q+1)=4 > Mult. both sides by (q+1)
16=4q+4 > Subtract 4 from both sides.
12=4q > Div. both sides by 4
q=3

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3 years ago

Please help me, because they ask for so many characters in Brainly lol

Andrej [43]

Answer:

$y=3x+5$

Step-by-step explanation:

Hi there!

Linear equations are typically organized in slope-intercept form: $y=mx+b$ where m is the slope and b is the y-intercept (the value of y when the line crosses the y-axis)

Given that the slope is 3, we can plug this into y=mx+b as m:

$y=3x+b$

Now, to solve for b, simply plug in the given point:

$-7=3(-4)+b\\-7=-12+b\\b=5$

Therefore, the y-intercept is 5. Plug this back into the equation:

$y=3x+5$

I hope this helps!

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2 years ago

What is the volume of a cylinder with a radius of 3 cm and a height of 5 cm?

PSYCHO15rus [73]

Answer:

141.3 cm³

Step-by-step explanation:

V=πr2h=π·32·5≈141.37167cm³

5 0

3 years ago

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The coordinate plane shows the floor plan for a swimming pool. What is the area of the pool’s border?"

emmasim [6.3K]

A = Area
L= Length = 15
W + widith = 10
A = 150
The pool area is L = 10
w= 5
A= 50
So the area of the perimeter = 100 square meters

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3 years ago

Read 2 more answers

In a one-way ANOVA, what is the difference between the among-groups variance MSA and the within-groups variance MSW?

LuckyWell [14K]

Answer:

$MSR=MSA=\frac{SSR}{k-1}$

And $MSE=MSW=\frac{SSE}{N-k}$

The difference is that MSA takes incount the variation between the groups and the grand mean, and the MSW takes in count the variation within groups respect to the mean of each group .

Step-by-step explanation:

Analysis of variance (ANOVA) "is used to analyze the differences among group means in a sample".

The sum of squares "is the sum of the square of variation, where variation is defined as the spread between each individual value and the grand mean"

If we assume that we have $j$ groups and on each group from $j=1,\dots,j$ we have $n_j$ individuals on each group we can define the following formulas of variation:

$SS_{total}=\sum_{j=1}^p \sum_{i=1}^{n_j} (x_{ij}-\bar x)^2$

$SS_{between=Treatment}=SS_{model}=\sum_{j=1}^p n_j (\bar x_{j}-\bar x)^2$

$SS_{within}=SS_{error}=\sum_{j=1}^p \sum_{i=1}^{n_j} (x_{ij}-\bar x_j)^2$

And we have this property

$SST=SS_{between}+SS_{within}=6750+8000=14750$

The degrees of freedom for the numerator on this case is given by $df_{num}=k-1$ where k represent the number of groups.

The degrees of freedom for the denominator on this case is given by $df_{den}=df_{between}=N-k$ .

And the total degrees of freedom would be $df=N-1$

We can find the $MSR=MSA=\frac{SSR}{k-1}$

And $MSE=MSW=\frac{SSE}{N-k}$

The difference is that MSA takes incount the variation between the groups and the grand mean, and the MSW takes in count the variation within groups respect to the mean of each group .

And the we can find the F statistic $F=\frac{MSR}{MSE}=$

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3 years ago