Respuesta :
Answer:
4
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
- Left to Right
Distributive Property
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtraction Property of Equality
Algebra I
- Terms/Coefficients
- Solving systems of equations using substitution/elimination
Step-by-step explanation:
Step 1: Define Systems
2x - y = 11
x + 3y = -5
Step 2: Rewrite Systems
2x - y = 11
- [Subtraction Property of Equality] Subtract 2x on both sides: -y = 11 - 2x
- [Division Property of Equality] Divide -1 on both sides: y = 2x - 11
Step 3: Redefine Systems
y = 2x - 11
x + 3y = -5
Step 2: Solve for x
Substitution
- Substitute in y [2nd Equation]: x + 3(2x - 11) = -5
- [Distributive Property] Distribute 3: x + 6x - 33 = -5
- Combine like terms: 7x - 33 = -5
- [Addition Property of Equality] Add 33 on both sides: 7x = 28
- [Division Property of Equality] Divide 7 on both sides: x = 4
Answer:
x = 4
Step-by-step explanation:
2x - y = 11
x + 3y = -5
To calculate the value of x , firstly we need to find value of y.
solve for y
- 2x - y = 11
subtract 2x from both side
- 2x - 2x - y = 11 - 2x
- -y = 11 - 2x
change the sign of both side of equation
- y = -11 + 2x
rewrite
- y = 2x - 11
Solve for x
- y = 2x - 11
- x + 3y = -5
substitute the value of y in the equation
- x + 3( 2x - 11 ) = -5
distribute 3
- x + 3 × 2x - 3× 11 = -5
- x + 6x - 33 = -5
combine like terms
- 7x - 33 = -5
Add 33 on both side
- 7x - 33 + 33 = -5 + 33
- 7x = 28
divide both side by 7
- 7x / 7 = 28 / 7
- x = 4
