Algebra: Chapter 2, Lesson 4, page 71.
Subtraction of Rational Numbers
Today, we are working on subtraction of rational numbers. Remember, just do the inverse of subtraction and ADD the inverse (or opposite) of the number to the other number.
Examples:
`2-6 = 2 + (-6) = -4`
`-5 – 7` is really `-5 + (-7)`, remembering that the + sign is invisible. So this becomes just `-5 + (-7)` and remembering the adding rule of 2 negatives, the answer becomes `-12`.
`-4 – (-5)` is really `-4 + 5` because 2 negative are a positive (bling-bling or make change-change from Ms. Phillips and Ms. Craig) and the answer is `+5 – 4` and the final answer is `+1`!
Two of tonight’s homework problems solved by MrE are here! Just click it!
Hotmath.com has these tutorials for the addition and subtraction of rational numbers too!
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Algebra 1a: Chapter 1, Lesson 7, page 33.
Solving Equations, An Introduction
An EQUATION is a mathematical sentence that uses the equal sign `=` to state that 2 expressions represent the same number or are equivalent. An equation that contains at least 1 variable is called an OPEN SENTENCE.
The set of numbers from which you can select replacements for the variable is called the REPLACEMENT SET, usually noted with squiggly brackets `{2, 5, 12}`. A replacement for a variable that makes an equation true is called the SOLUTION. To SOLVE and equation means to find all of its solutions. The collection of all the solutions is called the SOLUTION SET, usually contained in the { brackets}.
2 equations are EQUIVALENT if one can be obtained from the other by a sequence of the following steps. You can:
- add the same number to both sides of an equation
- subtract the same number from both sides of an equation
- multiply both sides of an equation by the same number
- divide both sides of an equation by the same number
Equivalent equations have the same solutions set.
Two of tonight’s homework problems solved by MrE are here! Just click it!!