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3 years ago

12

Find the 9th term of the arithmetic sequence with a 10 and d= -1/2

1 answer:

VLD [36.1K]3 years ago

5 0

a=10

d=-1/2

nth term=a+(n-1)d

10+(9-1)(-1/2)

10-4 =6

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What's the q1 and q2????

Evgen [1.6K]

Answer:

Q1-298

Q2-422

Step-by-step explanation:

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2 years ago

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Find three positive numbers whose sum is 140 and whose product is a maximum. (Enter your answers as a comma-separated list.)

Paladinen [302]

Answer:

$\frac{140}{3}, \frac{140}{3}, \frac{140}{3}$

Step-by-step explanation:

Let the numbers be $x, y\ and\ z.$

Such that:

$x + y + z = 140$

Make z the subject

$z = 140 -x - y$

For their product to be maximum, we have:

$f(x,y,z) = xyz$

Substitute $z = 140 -x - y$ in $f(x,y,z) = xyz$

$f(x,y) = xy(140 - x - y)$

Open bracket

$f(x,y) = 140xy - x^2y - xy^2$

Differentiate w.r.t x and y

$f_x=140y - 2xy - y^2$

$f_y=140x - x^2 - 2xy$

Since the products are maximum, then $f_x = f_y = 0$

For $f_x=140y - 2xy - y^2$

$140y - 2xy - y^2 = 0$

Factorize:

$y(140 - 2x - y) = 0$

Split

$y = 0\ or\ 140 - 2x - y = 0$

Make y the subject

$y = 0\ or\ y = 140 - 2x$

For $f_y=140x - x^2 - 2xy$

$140x - x^2 - 2xy = 0$

---------------------------------------------------

Substitute y = 0

$140x - x^2 -2x*0 = 0$

$140x - x^2 = 0$

Factorize

$x(140 - x)= 0$

$x = 0\ or\ 140-x = 0$

$x = 0\ or\ x = 140$

---------------------------------------------------

Substitute $y = 140 - 2x$

$140x - x^2 - 2xy = 0$

$140x - x^2 - 2x(140 - 2x) = 0$

$140x - x^2 - 280x + 4x^2 = 0$

Re-arrange

$4x^2 -x^2 +140x - 280x = 0$

$3x^2 -140x = 0$

Factor x out

$x(3x - 140) = 0$

Divide through by x

$3x - 140 = 0$

$3x = 140$

$x = \frac{140}{3}$

Recall that: $y = 140 - 2x$

$y = 140 - 2 * \frac{140}{3}$

$y = 140 - \frac{280}{3}$

Take LCM

$y = \frac{140*3-280}{3}$

$y = \frac{140}{3}$

Recall that:

$z = 140 -x - y$

$z = 140 - \frac{140}{3} - \frac{140}{3}$

Take LCM

$z = \frac{3 * 140- 140 - 140}{3}$

$z = \frac{140}{3}$

Hence, the numbers are:

$\frac{140}{3}, \frac{140}{3}, \frac{140}{3}$

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Two fifths times ten

babymother [125]

2/5 * 10 = 2/5 * 10/1 = 20/5 = 4

Answer is 4

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Complete each congruency statement and name the rule used. If you cannot show the triangles are congruent from the given informa

irinina [24]

Answer:

The correct answer is;

ΔANT ≅ ΔFLE by the SIde-Side-Side (SSS) rule of congruency

Step-by-step explanation:

The given information are;

Segment TN is congruent ts segment EL

Segment TA is congruent ts segment EF

Segment AN is congruent ts segment FL

Therefore, triangle ΔANT is congruent to ΔFLE by the Side-Side-Side (SSS) rule of congruency

One of the rule used to serve as proof that two or more triangles are congruent, is the Side-Side-Side (SSS) rule of congruency. The Side-Side-Side rule of congruency states that if the dimensions of the three sides of one triangle are equal to the dimensions of the three sides of another triangle, the two triangles are congruent.

Therefore, the correct option is ΔANT ≅ ΔFLE by the Side-Side-Side (SSS) rule of congruency

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How many different three-digit numbers can be formed which contain two digits that are the same, and a third digit that is diffe

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Tricky question. What are you trying to figure out?

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