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2 years ago

9) y = 7x - 20 3x + 8y = 17 For substitution

Mathematics

1 answer:

xenn [34]2 years ago

3 0

X=3
y=1
Use substitution method starting with the first equation substitute y in the second equation

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Which is the least common denominator of 5/6 3/8

Tems11 [23]

To find the least common denominator, or lcd, you have to find the least common multiple, or lcm. To do that you find the multiples of each number until they equal each other. I set up a chart like this,

6 -

8 -

and then I start listing multiples so,

6 - 6, 12, 18, 24,

8 - 8, 16, 24,

I stop after I find a number they are both equal to. So to get to that number I would multiply 8 by 3, and 6 by 4. This gives me 24 as the lcd. If you need the lcd to add the fractions together, then whatever you did to the bottom do to the top. So 5/6 would become 20/24 and 3/8 would become 9/24.

Answer: 24

4 0

3 years ago

The sum of the reciprocals of two consecutive even integers is 7/24. Write an equation that can be used to find the two integers

sergejj [24]

Assume the first even integer is x.
The next even integer will be 2 digits after this digit. So the next even integer will be x+2.

The reciprocals of these two even integers can be written as $\frac{1}{x}$ and $\frac{1}{x+2}$ respectively.

The sum of their reciprocals is 7/24. So we can set up the equation as:

$\frac{1}{x}+ \frac{1}{x+2}= \frac{7}{24}$

Taking LCM on left hand side:

$\frac{x+2+x}{x(x+2)}= \frac{7}{24} \\ \\ 
 \frac{2x+2}{ x^{2} +2x}= \frac{7}{24}$

Cross Multiplying the denominators:

$24(2x+2)=7({ x^{2} +2x}) \\ \\ 
48x+48=7 x^{2} +14x \\ \\ 
7 x^{2} +14x-48x-48=0 \\ \\ 
7 x^{2} -34x-48=0 \\ \\ 

$

Using the quadratic formula to solve the above equation:
$7 x^{2} -34x-48=0 \\ \\ 
x= \frac{34+- \sqrt{1156+1344} }{14} \\ \\ 
x= \frac{34+- \sqrt{2500} }{14} \\ \\ 
x=\frac{34+-50 }{14} \\ \\ 
x=6 \\ x=- \frac{8}{7} 
$

Since, the value of x can only be an integer, we discard the fractional value and keep x=6

So the first even integer is 6 and the next even integer is 8. The sum of reciprocals of 6 and 8 is 7/24

5 0

3 years ago

Lol help please ill give brainly to whoever helps

Solnce55 [7]

Get a better picture I’ll help then

7 0

2 years ago

I want to now what equals 64 please

ale4655 [162]

1 x 64=64 2 x 32=64 4 x 16 =64 8x8=64

3 0

2 years ago

Read 2 more answers

of 360 consumers polled some purchase ice cream some purchase frozen yogurt and some purchase both if 260 people polled purchase

uysha [10]

Answer: There are 350 consumers who purchase frozen yogurt.

Step-by-step explanation:

Since we have given that

Number of consumers polled =360

Number of consumers who purchased ice- cream = 260

Number of consumers who purchased both ice- cream and frozen yogurt = 250

We need to find the number of consumers who purchased frozen yogurt,

Let A denotes who purchased ice-cream

and B denotes who purchased frozen yogurt.

As we know the formula

$n(A\cup B)=n(A)+n(B)-n(A\cap B)\\\\360=260+n(B)-250\\\\360=10+n(B)\\\\360-10=n(B)\\\\350=n(B)$

Hence, there are 350 consumers who purchase frozen yogurt.

4 0

2 years ago