Algebra I For Dummies, 2nd Edition (For Dummies (Lifestyle))

Product Information

Multiply 4 x 6 x 2 x 3 = 144. This method doesn’t tell you what all the routes are; it just tells you how many are possible so you know when you’ve listed all of them. (Better get to work on that.)

Divisibility by 3:A number is divisible by 3 if the sum of the digits in the number is divisible by 3. Divisibility by 11:A number is divisible by 11 if the sums of the alternate digits are different by 0, 11, 22, or 33, or any two-digit multiple of 11. In other words, say you have a six-digit number: Add up the first, third, and fifth digits — the odd ones. Then add the digits in the even places — second, fourth, and sixth. Then subtract the smaller of those totals from the larger total, and if the answer is a multiple of 11, the original number is divisible by 11. A matrix is a rectangular array of numbers. Each row has the same number of elements, and each column has the same number of elements. Matrices can be classified as: square, identity, zero, column, and so on. You can multiply many exponential expressions together without having to change their form into the big or small numbers they represent. When multiplying exponents, the only requirement is that the bases of the exponential expressions have to be the same. So, you can multiply If one of these methods doesn’t work, then the binomial doesn’t factor by using real numbers. Factoring quadratic trinomials

Algebra I For Dummies, 2nd Edition (9781119293576) was previously published as Algebra I For Dummies, 2nd Edition (9780470559642). While this version features a new Dummies cover and design, the content is the same as the prior release and should not be considered a new or updated product. In algebra, an improper fraction is one where the numerator (the number on the top of the fraction) has a value greater than or equal to the denominator (the number on the bottom of the fraction) — the fraction is top heavy. To change a mixed number to an improper fraction, you need to multiply the whole number times the denominator and add the numerator. This result goes in the numerator of a fraction that has the original denominator still in the denominator. Multiply: 12 x 8 x 5 x 6 x 2 = 5,760. Don’t forget that soup or salad is two choices for that selection. If there’s more than one base in an expression with powers, you can combine the numbers with the same bases, find the values, and then write them all together. For example,

where N is a number between 1 and 10, but not 10 itself, and a is an integer (positive or negative number). Divisibility by 4:A number is divisible by 4 if the last two digits in the number form a number divisible by 4. Just be sure that whatever you do to one side of the equation, you also do to the other side. Think of the equation as two expressions pivoting on either side of a balance scale: You need to keep the sides at the same weigh t . Quadratic EquationsIf you can do task one in m1 ways, task two in m2 ways, task three in m3 ways, and so on, then you can perform all the tasks in a total of m1 · m2 · m3 . . . ways.