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9 months ago

the rule for being the nth item in a certain sequence is n(n+1)/2. what is the 4th term in this sequence ? a.) 4b.)10c.)16d.)20

Mathematics

1 answer:

abruzzese [7]9 months ago

3 0

The 4th term of the sequence can be determined as,

$\begin{gathered} a_n=\frac{n(n+1)}{2} \\ a_4=\frac{4(4+1)}{2} \\ a_4=10 \end{gathered}$

Thus, option (b) is correct.

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Zack bought a coat for $69.78. He paid with a $100 bill and received $26.73 in change.How Much was the sales tax? Show your work

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3 years ago

A foot ball field measures 100m by 72m. A school marks a football field similar in shape to a fullsize football field but only 3

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Given

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2 years ago

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Answer:

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2 years ago

Write a polynomial expression, in simplified form, that represents the AREA of the blanket and use the expression to evaluate th

pochemuha

Answer:

Polynomial expression that represents the area of blanket:

$A(x)=(6x^2+5x-21)cm^2$

If $x=2$ : $A(2)=13cm^2$

Step-by-step explanation:

The area of the rectangle can be calculated with the formula:

$A=lw$

Being l the lenght of the rectangle and w the width of the rectangle.

In this case, the lenght and the width are represented with:

$l=(3x+7)cm$

$w=(2x-3)cm$

Substitute them into $A=lw$ :

$A(x)=(3x+7)(2x-3)$

Then:

Use Distributive property (Remember the Product of powers property: $b^a*b^c=b^{(a+c)}$ ):

$A(x)=(3x+7)(2x-3)\\A(x)=6x^2-9x+14x-21$

Add like terms:

$A(x)=(6x^2+5x-21)cm^2$ (Simplied form)

Evaluate $x=2$ :

$A(2)=(6(2)^2+5(2)-21)cm^2\\A(2)=(6(4)+10-21)cm^2\\A(2)=(24-11)cm^2\\A(2)=13cm^2$

6 0

3 years ago