8.1 · Part II
Supported Application · Guided Entry to Today's Problem
Write Equations · Equation
- An equation is a mathematical sentence stating two expressions are equal
- A solution is a value for the variable that makes the equation true
- Check: Substitute the value into the equation and verify that both sides balance
- Write Equations (Escribir ecuaciones) — Represent a relationship with expressions joined by an equal sign.
- Equation (Ecuación) — A math sentence with an equal sign showing both sides are the same.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- Equal sign (Signo igual) — The = sign, showing both sides are the same.
- Expression (Expresión) — A math phrase with numbers and letters, but no equal sign.
- Constant (Constante) — A fixed number in an expression or equation that does not change.
- A common mistake in Write Equations is writing subtraction and division clues in the wrong order — putting the number from the clue first instead of the variable first. For 'a number decreased by 8 equals 5,' students often write 8 − n = 5 instead of the correct n − 8 = 5; for 'a number divided by 4 equals 6,' they write 4 ÷ n (or 4n) instead of n / 4 = 6. Always start with the variable, then attach the operation in the order the words describe it, and check by substituting your answer back in.
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1 MULTIPLE CHOICE
Is n = 3 a solution of n + 5 = 9?
- ANo, because 3 + 5 = 8, which does not equal 9
- BYes, because 3 is smaller than 9
- CYes, because 3 + 5 is close to 9
- DYou cannot tell without solving first
✏️ Workspace & Solution Steps -
2 MULTIPLE CHOICE
Which equation represents: 'A number divided by 4 equals 8'?
- An / 4 = 8
- B4n = 8
- Cn − 4 = 8
- Dn + 4 = 8
✏️ Workspace & Solution Steps
Writing Task: Justify why your mathematical solution is accurate and complete.
8.1 · Part II
On-Level Application · Standard Rigor
Write Equations · Equation
- An equation is a mathematical sentence stating two expressions are equal
- A solution is a value for the variable that makes the equation true
- Check: Substitute the value into the equation and verify that both sides balance
- Write Equations (Escribir ecuaciones) — Represent a relationship with expressions joined by an equal sign.
- Equation (Ecuación) — A math sentence with an equal sign showing both sides are the same.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- Equal sign (Signo igual) — The = sign, showing both sides are the same.
- Expression (Expresión) — A math phrase with numbers and letters, but no equal sign.
- Constant (Constante) — A fixed number in an expression or equation that does not change.
- A common mistake in Write Equations is writing subtraction and division clues in the wrong order — putting the number from the clue first instead of the variable first. For 'a number decreased by 8 equals 5,' students often write 8 − n = 5 instead of the correct n − 8 = 5; for 'a number divided by 4 equals 6,' they write 4 ÷ n (or 4n) instead of n / 4 = 6. Always start with the variable, then attach the operation in the order the words describe it, and check by substituting your answer back in.
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1 MULTIPLE CHOICE
A witness statement reads: 'A number c of security cameras plus 6 more equals 19.' Which equation matches?
- Ac + 6 = 19
- B6c = 19
- Cc − 6 = 19
- Dc / 6 = 19
✏️ Workspace & Solution Steps
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2 MULTIPLE CHOICE
A detective found some fingerprints on Monday and 14 more on Tuesday, for a total of 30. Which equation represents this?
- Af + 14 = 30
- Bf − 14 = 30
- C14f = 30
- Df / 14 = 30
✏️ Workspace & Solution Steps -
3 MULTIPLE CHOICE
Which equation represents: 'A number divided by 4 equals 8'?
- An / 4 = 8
- B4n = 8
- Cn − 4 = 8
- Dn + 4 = 8
✏️ Workspace & Solution Steps
Writing Task: Justify why your mathematical solution is accurate and complete.
8.1 · Part II
Extension & Non-Routine Application
Write Equations · Equation
- An equation is a mathematical sentence stating two expressions are equal
- A solution is a value for the variable that makes the equation true
- Check: Substitute the value into the equation and verify that both sides balance
- Write Equations (Escribir ecuaciones) — Represent a relationship with expressions joined by an equal sign.
- Equation (Ecuación) — A math sentence with an equal sign showing both sides are the same.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- Equal sign (Signo igual) — The = sign, showing both sides are the same.
- Expression (Expresión) — A math phrase with numbers and letters, but no equal sign.
- Constant (Constante) — A fixed number in an expression or equation that does not change.
- A common mistake in Write Equations is writing subtraction and division clues in the wrong order — putting the number from the clue first instead of the variable first. For 'a number decreased by 8 equals 5,' students often write 8 − n = 5 instead of the correct n − 8 = 5; for 'a number divided by 4 equals 6,' they write 4 ÷ n (or 4n) instead of n / 4 = 6. Always start with the variable, then attach the operation in the order the words describe it, and check by substituting your answer back in.
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1 MULTIPLE CHOICE
Marisol tests values in the equation 7 + m = 23. Which value of m makes the equation true?
- Am = 16
- Bm = 30
- Cm = 23
- Dm = 9
✏️ Workspace & Solution Steps -
2 MULTIPLE CHOICE
A torn note reads: 'A suspect's case minutes m, after 9 fewer, leaves 24.' Which equation fits?
- Am − 9 = 24
- Bm + 9 = 24
- C9m = 24
- Dm / 9 = 24
✏️ Workspace & Solution Steps
Writing Task: Justify why your mathematical solution is accurate and complete.