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3 years ago

X+2y=13 3x-5y=6 what is (x,y)?

Mathematics

2 answers:

tamaranim1 [39]3 years ago

5 0

Answer:

(7, 3)

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 = 13

3x - 5y = 6

Step 2: Rewrite Systems

x + 2y = 13

Subtract 2y on both sides: x = 13 - 2y

Step 3: Redefine Systems

x = 13 - 2y

3x - 5y = 6

Step 4: Solve for y

Substitution

Substitute in x: 3(13 - 2y) - 5y = 6
Distribute 3: 39 - 6y - 5y = 6
Combine like terms: 39 - 11y = 6
Isolate y term: -11y = -33
Isolate y: y = 3

Step 5: Solve for x

Define equation: x + 2y = 13
Substitute in y: x + 2(3) = 13
Multiply: x + 6 = 13
Isolate x: x = 7

scZoUnD [109]3 years ago

3 0

Answer:

x+2y=13

Step 1: Add -2y to both sides.

x+2y+−2y=13+−2y

x=−2y+13

Answer:

x=−2y+13

Step 1: Add 5y to both sides.

3x−5y+5y=6+5y

3x=5y+6

Step 2: Divide both sides by 3.

5y+6

y+2

Answer:

y+2

Step 1: Add -3x to both sides.

3x−5y+−3x=6+−3x

−5y=−3x+6

Step 2: Divide both sides by -5.

−5y

−5

−3x+6

−5

−6

Answer:

−6

Step-by-step explanation:

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a. Note that $f(x)=x^ne^{-2x}$ is continuous for all $x$ . If $f(x)$ attains a maximum at $x=3$ , then $f'(3) = 0$ . Compute the derivative of $f$ .

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<h3>What is percentage ?</h3>

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