MA19.4.28a
Describe right triangles as a category, and identify right triangles.
Describe right triangles as a category, and identify right triangles.
Describe right triangles as a category, and identify right triangles.
Define a line of symmetry for a two-dimensional figure as a line across the figure such that the figure can be folded along the line into matching parts.
Identify line-symmetric figures and draw lines of symmetry.
Write, explain, and evaluate simple numerical expressions involving the four operations to solve up to two-step problems. Include expressions involving parentheses, brackets, or braces, using commutative, associative, and distributive properties.
Generate two numerical patterns using two given rules and complete an input/output table for the data.
Use data from an input/output table to identify apparent relationships between corresponding terms.
Form ordered pairs from values in an input/output table.
Graph ordered pairs from an input/output table on a coordinate plane.
Using models and quantitative reasoning, explain that in a multi-digit number, including decimals, a digit in any place represents ten times what it represents in the place to its right and $\frac{1}{10}$ of what it represents in the place to its left.
Explain patterns in the number of zeros of the product when multiplying a number by powers of 10, using whole-number exponents to denote powers of 10.
Explain patterns in the placement of the decimal point when a decimal is multiplied or divided by a power of 10, using whole-number exponents to denote powers of 10.
Read, write, and compare decimals to thousandths.
Read and write decimals to thousandths using base-ten numerals, number names, and expanded form.
Example: $347.392 = 3 \times 100 + 4 \times 10 + 7 \times 1 + 3 \times (\frac{1}{10}) + 9 \times (\frac{1}{100}) + 2 \times (\frac{1}{1000})$.
Compare two decimals to thousandths based on the meaning of the digits in each place, using >, =, and < to record the results of comparisons.
Use place value understanding to round decimals to thousandths.
Fluently multiply multi-digit whole numbers using the standard algorithm.
Use strategies based on place value, properties of operations, and/or the relationship between multiplication and division to find whole-number quotients and remainders with up to four-digit dividends and two-digit divisors. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
Add, subtract, multiply, and divide decimals to hundredths using strategies based on place value, properties of operations, and/or the relationships between addition/subtraction and multiplication/division; relate the strategy to a written method, and explain the reasoning used.
Use concrete models and drawings to solve problems with decimals to hundredths.
Solve problems in a real-world context with decimals to hundredths.
Model and solve real-word problems involving addition and subtraction of fractions referring to the same whole, including cases of unlike denominators, using visual fraction models or equations to represent the problem. Use benchmark fractions and number sense of fractions to estimate mentally, and assess the reasonableness of answers.
Example: Recognize an incorrect result $\frac{2}{5} + \frac{1}{2} = \frac{3}{7}$ by observing that $\frac{3}{7} < \frac{1}{2}$.
Add and subtract fractions and mixed numbers with unlike denominators, using fraction equivalence to calculate a sum or difference of fractions or mixed numbers with like denominators.
Solve word problems involving division of whole numbers leading to answers in the form of fractions or mixed numbers.
Model and interpret a fraction as division of the numerator by the denominator ($\frac{a}{b} = a \div b$).
Use visual fraction models, drawings, or equations to represent word problems involving division of whole numbers leading to answers in the form of fractions or mixed numbers.
Apply and extend previous understandings of multiplication to find the product of a fraction times a whole number or a fraction times a fraction.
Use a visual fraction model (area model, set model, or linear model) to show $(\frac{a}{b}) \times q$ and create a story context for this equation to interpret the product as a parts of a partition of q into b equal parts.
Use a visual fraction model (area model, set model, or linear model) to show $(\frac{a}{b}) \times (\frac{c}{d})$ and create a story context for this equation to interpret the product.
Multiply fractional side lengths to find areas of rectangles, and represent fraction products as rectangular areas.
Find the area of a rectangle with fractional side lengths by tiling it with unit squares of the appropriate unit fraction side lengths to show that the area is the same as would be found by multiplying the side lengths.
Interpret multiplication as scaling (resizing).
Compare the size of a product to the size of one factor on the basis of the size of the other factor, without performing the indicated multiplication.
Example: Use reasoning to determine which expression is greater? 225 or $\frac{3}{4} \times 225$ ; $\frac{11}{50}$ or $\frac{3}{2} \times \frac{11}{50}$
Explain why multiplying a given number by a fraction greater than 1 results in a product greater than the given number and relate the principle of fraction equivalence.
Explain why multiplying a given number by a fraction less than 1 results in a product smaller than the given number and relate the principle of fraction equivalence.
Model and solve real-world problems involving multiplication of fractions and mixed numbers using visual fraction models, drawings, or equations to represent the problem.