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2 years ago

Solve the system by substitution. 3x +2y=-21 x+y=-9

Mathematics

1 answer:

galben [10]2 years ago

5 0

Answer:

Step-by-step explanation:

3x +2y=-21 and x+y=-9

3x +2y=-21 and x = -9-y

=> 3(-9 - y) + 2y = -21

-27 -3y + 2y = -21

-y = 6

y= -6

=> x = -9+6= -3

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3,984,896 rounded to the nearest hundred

ziro4ka [17]

Answer:

3,984,896 rounded to the nearest hundred is 3,984,900

4 0

3 years ago

What is the true solution to the equation below?

Naddik [55]

Yeeee

assuming your equaiton is
$2ln(e^{ln(2x)})-ln(e^{ln(10x)})=ln(30)$

remember some nice log rules
$log_a(b)=c$ translates to $a^c=b$
and
$a^{log_a(b)}=b$
and
$xlog_c(b)=log_c(b^x)$
and
$ln(x)=log_e(x)$
and
$log(a)-log(b)=log(\frac{a}{b})$
and
if $log(a)=log(b)$ then a=b

so

we can simplify a bit of stuff here

the $e^{ln(2x)} \space\ and \space\ the \space\ e^{ln(10x)}$ can be simplified to $2x \space\ and \space\ 10x$

so we gots now

$2ln(2x)-ln(10x)=ln(30)$
$ln((2x)^2)-ln(10x)=ln(30)$
$ln(4x^2)-ln(10x)=ln(30)$
$ln(\frac{4x^2}{10x})=ln(30)$
same base so
$\frac{4x^2}{10x}=30$
$\frac{2x}{5}=30$
times both sides by 5
$2x=150$
divide both sides by 2
$x=75$
answer is x=75

5 0

3 years ago

Answer!!!!! Help!!!

guajiro [1.7K]

Answer:

The answer is postulate

7 0

2 years ago

Mai and Tyler work on the equation 2/5b+1=-11 together. Mais soulution is b=-25 and Tyler’s is b=-28. Here is their work. Do you

Anika [276]

Answer:

No I don't agree with their solution; both their answers are wrong.

Correct answer is $b=-30$ .

Step-by-step explanation:

Given:

$\frac{2}{5}b+1=-11$

Now given:

According to Mai $b = -25$ and According to Tyler $b = -28$

Now we need to find which of them is correct.

So we will solve the given equation we get;

$\frac{2}{5}b+1=-11$

Subtracting both side by 1 we get;

$\frac{2}{5}b+1-1=-11-1\\\\\frac{2}{5}b =-12$

Now Multiplying both side $\frac{5}{2}$ we get;

$\frac{2}{5}b\times\frac{5}{2}= -12 \times \frac{5}{2}\\\\b=-6\times 5\\\\b=-30$

Hence both of them are incorrect, correct answer is $b=-30$ .

3 0

3 years ago

Find the x-intercept of the function f(x) = a^x + 1 - 1.

babymother [125]

I am not certain of what you wrote for the function but will assume that is likely exponential function or quadratic function.

First, (quadratic function) To solve this, you must know the quadratic formula. The x-intercept is value(s) that has the output value(y) of 0.

If the vertex of the quadratic function of (0,0), there is only one x-intercept. The number and value of the x-intercept depends on the slope and vertical displacement.

Second, (exponential function) note that there is no x-intercept. For instance, if a is 2, is there such value y that 2^y is 0? The smallest exponential value that is an integer is 1. Even broadening the limit to rational numbers, no such exponential value can have the result of 0. Therefore, in the basic form of exponential function, there is no x-intercept.

4 0

3 years ago