Day 140 – April 10

Algebra: Chapter 13, Lesson 2, page 580.

More Solving Quadratic Equations

Solve a quadratic equation of the form `ax^2 = k`

Example: `-3x^2 + 7 = 0` becomes …

`-3x^2 = -7` or `x^2=7/3`

then `x = ±sqrt(7/3)`, don’t forget to rationalize this to `x = ±sqrt(21)/3`!

Solve a quadratic equation by factoring one expression into a binomial square [of the form `(x + a)^2 = k`]

Example: `(x-5)^2 = 9`, if you take the square root of both sides becomes …

`x-5 = ±sqrt(9)` or `x = 5 ±sqrt(9)` or `x = 5 ± 3` or `x=8` or `x=2`

See here for more examples.

Two of tonight’s homework problems solved by MrE are here! Just click it.

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Algebra 1a: CST Review – Area of a Parallelogram, Triangle and Trapezoid

Definitions: `b` is the base and `h` is the height of the geometric figure below. Remember too, that the base and the height are at RIGHT ANGLES to each other!

Area, of a Triangle, `A = (b*h)/2` which is the same thing as `(1/2) * b * h`

Area of a Parallelogram, `A= b*h`.

Area of a Trapezoid, `A = (1/2) * h * (b_1 + b_2)` which is the same thing as `[h * (b_1 + b_2)]/2`

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