All categories

2 years ago

Substitution method...need help.. started but cant finish

Mathematics

1 answer:

trapecia [35]2 years ago

8 0

Solve either equation for either variable. Since the second one has y on its own, the easiest choice is to solve that for y.

-5x + y = 13 ⇒ y = 5x + 13

Now substitute this into the other equation to eliminate y and rewrite it entirely in terms of x :

-3x + 3y = 3 ⇒ -3x + 3 (5x + 13) = 3

Simplify and solve for x :

-3x + 15x + 39 = 3

12x = -36

x = -3

Substitute this into either original equation to solve for y. Plugging x = -3 into the first equation would give

-3 (-3) + 3y = 3

9 + 3y = 3

3y = -6

y = -2

So the solution to the system of equations is (x, y) = (-3, -2).

You might be interested in

Which number is a factor of 12 but not a multiple of 3?

Delvig [45]

First list all the factors of 12;

1, 2, 3, 4, 6, 12

now let's see which ones are multiples of 3;

3, 6, 12

so all we have left are numbers 1, 2 and 4.

hope that helps, God bless!

6 0

3 years ago

Which expressionism equivalent to -60 / 5 select all that apply 60 divided by negitive 5 60 times 1/5 60 times negitive 1/5 Negi

GaryK [48]

Answer:

Equivalent expressions

A) $\frac{60}{-5}$

C) $60\times (-\frac{1}{5})$

Step-by-step explanation:

Given expression :

$\frac{-60}{5}$

Choices given :

A) $\frac{60}{-5}$

B) $60\times \frac{1}{5}$

C) $60\times (-\frac{1}{5})$

D) $-60\times (-\frac{1}{5})$

To find the equivalent expression.

We will first evaluate the given expression.

$\frac{-60}{5}$

⇒ $-12$ [Quotient of a negative dividend and a positive divisor is always negative]

Evaluating each choice to select the equivalents.

A) $\frac{60}{-5}$

⇒ $-12$ [Quotient of a positive dividend and a negative divisor is always negative]

B) $60\times \frac{1}{5}$

⇒ $\frac{60}{5}$

⇒ $12$

C) $60\times (-\frac{1}{5})$

⇒ $-\frac{60}{5}$ [Product of a positive and a negative is always a negative]

⇒ $-12$

D) $-60\times (-\frac{1}{5})$

⇒ $\frac{60}{5}$ [Product of two negatives is always a positive]

⇒ $12$

∴ We see that the choices A and C are equivalent.

7 0

3 years ago

(4200 + 75) + 5 = ( ? )+ (75+5)<br> What would make it true?

geniusboy [140]

Answer:

4200

Step-by-step explanation:

4280=(?)+80

So the answer is 4200

8 0

3 years ago

Read 2 more answers

90. The number of daily evening newspapers in the United States has decreased by 46.5% to

aleksandr82 [10.1K]

Answer:

700

Step-by-step explanation:

Given:

Daily evening newspapers in 2015 = 389

Percentage decrease from 2000 to 2015 = 46.5%

To find:

Number of newspapers in 2000 = ?

Solution:

Let the number of newspapers in 2000 = $x$

When 46.5% of the total newspapers in 2000 ( $x$ ) is subtracted from the total newspapers in 2000 ( $x$ ), it will be equal to the number of newspapers in 2015.

Making the equation as per the given statement:

$x-x\times 46.5\%=389\\\Rightarrow \dfrac{100x-46.5x}{100}=389\\\Rightarrow 53.5x=38900\\\Rightarrow x\approx \bold{727}$

Therefore, the answer is:

There were <em>727 </em>newspapers in 2000.

7 0

3 years ago

Is 26,341 divisible by 9

Paul [167]

No, it would leave a decimal

6 0

3 years ago