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3 years ago

9 is the difference between two numbers, and their sum is 31. Find the numbers.

Mathematics

1 answer:

algol [13]3 years ago

4 0

Answer:

The first number is 20, the second one is 11

Step-by-step explanation:

Let the first number be x and the second number be y

Since it says "9 is the difference between two numbers", the first equation will be x-y=9

It also says that "their sum is 31". That means the second equation will be x+y=31

here are the two equations:

x-y=9

x+y=31

You can solve this any way you like, but I'll show elimination

add the two equations

x-y=9

x+y=31

2x=40

divide by 2

x=20

Substitute 20 as x in one of the equations

20+y=31

subtract 20 from both sides

y=11

That means the two numbers are 20 and 11

Hope this helps!

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Convert the decimal 0.8034 to a fraction and classify it as either rational or irrational.

Llana [10]

Answer:

Fractional form of 0.8034 $=\frac{4017}{5000}$

Since 4017 and 5000 are whole numbers this fraction is rational.

Step-by-step explanation:

We have $0.8034=\frac{8034}{10000} =\frac{4017}{5000}$

Fractional form of 0.8034 $=\frac{4017}{5000}$

Since 4017 and 5000 are whole numbers this fraction is rational.

7 0

3 years ago

A 5-gallon jug of cleaning solution contains 6% bleach. How much pure water should be added to it to dilute to 4% bleach?

mihalych1998 [28]

Let's bear in mind that 5 gallons with a solution of 6% bleach, contains some water plus some bleach, how much bleach? well, is just 6% of 5 gallons or namely (6/100) * 5 gallons, or 0.30 gallons.

if we use "x" gallons of water, well pure water has no bleach, so is 0% bleach, and it has a (0/100) * x or 0x gallons of bleach.

the mixture will be say "y" gallons, and is 4% bleach, so (4/100) * y is 0.04y gallons in the mixture of bleach.

$\bf \begin{array}{lcccl}
&\stackrel{gallons}{quantity}&\stackrel{\textit{\% of bleach}}{amount}&\stackrel{\textit{gallons of bleach}}{amount}\\
&------&------&------\\
\textit{pure water}&x&0.00&0x\\
\textit{6\% solution}&5&0.06&0.3\\
-----&------&------&------\\
mixture&y&0.04&0.04y
\end{array}
\\\\\\
\begin{cases}
x+5=\boxed{y}\\
0x+0.3=0.04y\\
---------\\
0.3=0.04\left( \boxed{x+5} \right)
\end{cases}
\\\\\\
0.3=0.04x+0.2\implies 0.1=0.04x\implies \cfrac{0.1}{0.04}=x\implies 2.5=x$

3 0

3 years ago

Tap on the thing and somebody help me with all this pls

Mumz [18]

Hey what number do you need help with

8 0

3 years ago

Solve the equation X³+2X²-5X -6

Natali [406]

Answer: x = {-1, -3, 2}

Step-by-step explanation:

x³ + 2x² - 5x - 6 = 0

Use the rational root theorem to find the possible roots: ±1, ±2, ±3, ±6

Use Long division, Synthetic division, or plug them into the equation to see which root(s) work (result in a remainder of zero).

I will use Synthetic division. Let's try x = 1

1 | 1 2 -5 -6

| ↓ 1 3 -2

1 3 -2 -8 ← remainder ≠ 0 so x = 1 is NOT a root

Let's try x = -1

- 1 | 1 2 -5 -6

| ↓ -1 -1 6

1 1 -6 0 ← remainder = 0 so x = -1 is a root!

The coefficients of the reduced polynomial are: 1, 1, -6 --> x² + x - 6

Factor: x² + x - 6

(x + 3)(x - 2)

Set those factors equal to zero to solve for x:

x + 3 = 0 --> x = -3

x - 2 = 0 --> x = 2

Using Synthetic Division and Factoring the reduced polynomial, we found

x = -1, -3, and 2

6 0

2 years ago

What is the taxidistance between (2,11) and (7,10) 4 6 7 26

Scilla [17]

X difference: 7-2 = 5 y difference: 11-10 = 1 Add up those results: 5+1 = 6

Answer Is 6

4 0

3 years ago