options: Understand addition as putting together and adding to, and understand subtraction as taking apart and taking from.

Solve equations and inequalities in one variable.

Work with radicals and integer exponents.

Analyze patterns and relationships.

Use properties of operations to generate equivalent expressions.

Apply and extend previous understandings of arithmetic to algebraic expressions.

Understand the relationship between zeros and factors of polynomials.

Write and interpret numerical expressions.

Perform arithmetic operations on polynomials.

Understand the connections between proportional relationships, lines, and linear equations.

Interpret the structure of expressions.

Solve problems involving the four operations, and identify and explain patterns in arithmetic.

Reason about and solve one-variable equations and inequalities.

Represent and solve problems involving addition and subtraction.

Work with addition and subtraction equations.

Generate and analyze patterns.

Understand properties of multiplication and the relationship between multiplication and division.

Work with equal groups of objects to gain foundations for multiplication.

Use the four operations with whole numbers to solve problems.

Create equations that describe numbers or relationships

Rewrite rational expressions.

Multiply and divide within 100.

Gain familiarity with factors and multiples.

Understand and apply properties of operations and the relationship between addition and subtraction.

Represent and analyze quantitative relationships between dependent and independent variables.

Analyze and solve linear equations and pairs of simultaneous linear equations.

Understand solving equations as a process of reasoning and explain the reasoning.

Use polynomial identities to solve problems.

Solve systems of equations.

Write expressions in equivalent forms to solve problems.

Represent and solve problems involving multiplication and division.

Add and subtract within 20.

Represent and solve equations and inequalities graphically.

Solve real-life and mathematical problems using numerical and algebraic expressions and equations.
problem_activity: Potassium-40 has a half-life of
$${1.28\times 10^9}$$
years, which means that after that many years, half of a sample has decayed into a different isotope of carbon. If a sample began with
$${115}$$
grams of potassium-40
$${30,000,000}$$
years ago, how much is left today? How long will it be until there are only
$${50}$$
grams remaining?


correct_option_index: 10