All categories

2 years ago

Divid 15 into two parts such that the sum of their reciprocal is 3/10

1 answer:

4 0

Let x and y be the 2 parts of 15 ==> x + y=15 (given)

Reciprocal of x and y ==> 1/x +1/y ==> 1/x + 1/y = 3/10 (given)

Let's solve 1/x + 1/y = 3/10 . Common denominator = 10.x.y (reduce to same denominator)

==> (10y+10x)/10xy = 3xy/10xy ==> 10x+10y =3xy

But x+y = 15 , then 10x+10y =150 ==> 150=3xy and xy = 50

Now we have the sum S of the 2 parts that is S = 15 and
their Product = xy =50
Let's use the quadratic equation for S and P==> X² -SX +P =0
Or X² - 15X + 50=0, Solve for X & you will find:
The 1st part of 15 is 10 & the 2nd part is 5

You might be interested in

Find the equation of the line. <br><br> GIVING BRAINIEST TO WHOEVER HELPS ME AND GETS IT RIGHT!!!

Anestetic [448]

Answer:

y= -3x + 7

Step-by-step explanation:

y intercept= 7

slope= -3

3 0

2 years ago

Read 2 more answers

Work out 1 3/4 x 4 1/6

sattari [20]

Convert mixed number to improper fraction:

$1\dfrac{3}{4}=\dfrac{1\cdot4+3}{4}=\dfrac{4+3}{4}=\dfrac{7}{4}\\\\4\dfrac{1}{6}=\dfrac{4\cdot6+1}{6}=\dfrac{24+1}{6}=\dfrac{25}{6}\\\\1\dfrac{3}{4}\times4\dfrac{1}{6}=\dfrac{7}{4}\times\dfrac{25}{6}=\dfrac{7\times25}{4\times6}=\dfrac{175}{24}=\dfrac{168+7}{24}=7\dfrac{7}{24}$

8 0

3 years ago

Sara has agreed to help with her younger sister's science fair experiment. Her sister planted string beans in two pots. She is

Delvig [45]

Answer: plants are same height in 30 days; Plant A is tallest in 6 weeks

Step-by-step explanation:

x = number of days

4 + (2/3)x = 9 + (1/2)x

(2/3)x - (1/2)x = 9 - 4

(1/6)x = 5

x = 30, number of days for Plant A and Plant B to be same height.

6 wks = 42 days

Plant A in 42 days: 4 + (2/3)(42) = 32 inches

Plant B in 42 days: 9 + (1/2)(42) = 30 inches

7 0

5 months ago

5(2x+6)=-4(-5-2x)+3x step by step

Oksi-84 [34.3K]

Answer:

x = 10

Step-by-step explanation:

Okay, let's solve :)

So first we have to distribute on the left side(it doesn't matter which side FYI)

When we do, we have :

10x + 30 = -4(-5-2x)

Now we distribute on the right side! Remember, negative * negative = positive.

10x + 30 = 20 + 8x + 3x

Let's simplify on the right side to

10x + 30 = 20 + 11x

Now, let's subtract 10x on both sides to get

x + 20 = 30(i simply flipped the equation)

Subtract 20 on both sides to get!

x = 10!

5 0

2 years ago

Hi whats <br> u = x - k solve for x

kykrilka [37]

Answer:

x=u+k

Step-by-step explanation:

4 0

1 year ago

Read 2 more answers