Algebra: Chapter 8, Lesson 6, page 387.
Digit and Coin word problems.
Just remember to write the coin problems with the d (dime), q (quarter), n (nickel) preceeded by the value of the coin remembering that the d, q or n stand for the number of that type of coin. For example, `.05n + .10d = 2.05`. You can then multiply both sides by `100` to clear the decimals.
Remember too, that any 2-digit number can be expressed as `10x + y` where `x` is the digit in the tens place and `y` is the digit in the one (units) place. For example, the number `23` can be written as `10 * 2 + 3`. If we reverse the digits in the original number, the new number can be expressed as `10y + x`. The reverse of `23`, `32` can be written as `10 * 3 + 2`.
Here is a link for some examples of coin problems and here is a link for digit type problems (about 1/2 the way down the page)!
Two of tonight’s homework problems solved by MrE are here! Just click it!
======================================================================
Algebra 1a: Chapter 3, Lesson 8, page 145.
Solving Equations Involving Absolute Value
The absolute value of a number, `|x|` is its distance from zero on the number line. Remember that the absolute value is always positive. Treat absolute value equations just like those without absolute value and then solve them as normal. At the VERY END, put the absolute value symbols back in and see if the answer has ANOTHER solution.
Remember too, that we cannot have an absolute value be NEGATIVE. In these cases, there is NO SOLUTION. For example:
`|x| + 2 = 12`
`|x| + 2 + (-2) = 12 + (-2)`, we subtract 2 from both sides to isolate the variable, x
`|x| = 10`, we simplify the right side and finally,
`x=10` or `x=-10` are the solutions
This is a good purplemath.com link with examples.
Two of tonight’s homework problems solved by MrE are here! Just click it!