The difference between x<br> and half of y.

How do i solve systems of equations by elimination?

Vera_Pavlovna [14]

Say you had this problem:

-4x - 2y= -12
4x +8y = -24

First you would have to cancel out one part of the equation to get on variable alone. In this case it's easy it would be -4x and 4x. So then you would cancel those out.

Now we have

-2y= -12
8y =-24

so then you just add them all up

6y=-36

Next you just divide both sides by 6
so then you answer for y would be -6.

Next you would choose one of your equations and plug the -6 in.

So it would be

-4x -2 (-6) =-24

So you would times negative 2 by negative 6, which would be positive 12. Since a negative times a negative equales a positive.

-4x + 12= -24

Next you would minus 12 on both sides.

-4x + 12=-24
- 12 = -12

The 12's would cancel out and then you just minus -24 by -12 which you would ended up just plusing them together because a negative plus a negative equales a negative. Or a negative minus a negative number would end up adding them up.

-4x= -36

Next you would get x alone and how you would do that is you would divide -4 in both sides which would cancel them -4 out then it would be divided by -36.

So it would look like this.

-4x= -36
-4 -4

So negative 36 divided by negative 4 is 9.

So your final answer would be

y= -6
x= 9

I hope I explained to you properly how to do systems of equations by elimination.

8 0

3 years ago

Which expression is equivalent to RootIndex 3 StartRoot StartFraction 75 a Superscript 7 Baseline b Superscript 4 Baseline Over

slega [8]

Answer:

B. $\frac{b}{2a^{2}c^3}\sqrt[3]{15b}$

Step-by-step explanation:

Given:

The expression to simplify is given as:

$\sqrt[3]{\frac{75a^7b^4}{40a^{13}c^9}}$

Use the exponent property $\frac{a^m}{a^n}=a^{m-n}$

$\frac{a^7}{a^{13}}=a^{7-13}=a^{-6}$

Use the exponent property $(a^m)^n=a^{m\times n}$

$a^{-6}=a^{-2\times 3}=(a^{-2})^3$

$b^4=b\times b^3\\c^{9}=(c^3)^3$

Reducing $\frac{75}{40}$ to simplest form, we get:

$\frac{5\times 5\times 3}{2^3\times 5}=\frac{15}{2^3}$

Therefore, expression becomes:

$\sqrt[3]{\frac{15(a^{-2})^3\times b\times b^3}{2^3(c^3)^3}}$

Use the cubic root property:

$\sqrt[3]{x^3} =x$ . Thus, the expression becomes:

$\frac{a^{-2}b}{2c^3}\sqrt[3]{15b}$

Using the exponent property $a^{-m}=\frac{1}{a^m}$

$a^{-2}=\frac{1}{a^2}$

So, the final expression is:

$\frac{b}{2a^{2}c^3}\sqrt[3]{15b}$

Therefore, the correct option is option B.

7 0

4 years ago

How do I simplify 3(2a-8b)

Mumz [18]

You would have to do distribution. So you would have to multiply 3 by 2a and multiply 3 by -8b. 3 times 2a equals 6a (always keep the letter) and 3 times -8b equals -24b. (if there is only one negative number when multiplying, always keep the negative sign.) now you are left with 6a-24b. and since we cant put a into b, your answer would be 6a-24b. hopefully this helped you and sorry if it confused you

4 0

4 years ago

Read 2 more answers

Which expression is equivalent to 3(x + 4y)?

RUDIKE [14]

Just distribute the 3. 3(x + 4y) = 3x + 12y

3x + 12y is the answer.

4 0

4 years ago

HELP PLEASE MY WORK HAS TO BE DUE IN A FEW MINUTES PLEASE HELP

PilotLPTM [1.2K]

Given: 2/3 every 30 seconds

If we cut 2/3 in half, we get 1/3. This would also mean we cut the time in half 30 / 2 = 15 seconds

Therefore, 1/3 of the length every 15 seconds.

15 + 15 + 15 = 45 seconds to go the full length of the path

3 0

3 years ago

The difference between x and half of y.