Mathematics, 20.12.2020 17:40, ThePotato381

Solve by using elimination. Express your answer as an ordered pair.

Answers: 3

Show answers

Answers

answered: sharperenae463

(-2, 0)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right

Equality Properties

Algebra I

Solving systems of equations using substitution/elimination

Step-by-step explanation:

Step 1: Define Systems

-x - 2y = 2

4x - 2y = -8

Step 2: Rewrite Systems

-x - 2y = 2

Multiply both sides by -1: x + 2y = -2

Step 3: Redefine Systems

x + 2y = -2

4x - 2y = -8

Step 4: Solve for x

Elimination

Combine equations: 5x = -10Divide 5 on both sides: x = -2

Step 5: Solve for y

Define equation: 4x - 2y = -8Substitute in x: 4(-2) - 2y = -8Multiply: -8 - 2y = -8Isolate y term: -2y = 0Isolate y: y = 0

answered: mamdouh2893

Greetings again.

The answer is (-2,0)

Explanation:

This one is different from other 2 previous questions. The last and previous 2 questions have positive y for another equation and negative y for another equation which makes them 0 (As y - y = 0)

But this one is different. y-terms both are negative for both equations. If we decide to add -2y and -2y then It'd make -4y which doesn't make 0.

And how are we gonna solve by elimination? That's simple. By multiplying one of the equation by -1.

We can do that, to eliminate y-term out. Choose one equation to multiply. I'll be multiplying -1 in the first equation.

-x-2y=2

Multiply -1 in whole equation.

$-x(-1)-2y(-1)=2(-1)\\x+2y=-2$

Remind that negative multiply/distribute in negative equal positive always.

And x + 2y = -2 is your new equation from the first equation.

$\left \{ {{x+2y=-2} \atop {4x-2y=-8}} \right.$

This is our new equations. Then we are able to eliminate y-term.

$5x=-10\\x=-2$

In case if you forget again, we can simply add/subtract vertically.

x+4x = 5x

2y-2y = 0

-2-8 = -10

That's how we get 5x=-10 and thus x = -2.

We already get x-value, and you know that we need to find the y-value too.

Therefore, substitute x = -2 in any given equations. Less coefficient value, the faster and better.

I'll substitute in -x-2y=2

-x-2y=2

Substitute x = -2 in the equation.

$-(-2)-2y=2\\2-2y=2\\-2y=2-2\\-2y=0\\y=\frac{0}{-2}\\y=0$

Thus, when x = -2, y = 0. Since you want the answer as ordered pair, then the answer is (-2,0)

answered: Guest

This does not make sense

answered: Guest

according to the triangle sum theorem, all the angles in a triangle must add up to 180 degrees. if we know one angle is already 90, we do 180-90=90. the other 2 angles must add up to 90, exactly.

step-by-step explanation:

Other questions on the subject: Mathematics

Mathematics, 21.06.2019 13:30, love0000

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

Answers: 1

continue

Mathematics, 21.06.2019 14:40, offensiveneedle

1. what is the phythaforean theorem? 2.what do we use it for? 1.what is the distance formula ? 2.what do we use it for?

Answers: 2

continue

Mathematics, 21.06.2019 18:00, joshuahagerman1404

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.

Answers: 3

continue

Mathematics, 21.06.2019 19:30, kelseybell2707

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).