How to find the area of regular polygons, given only the apothem?
I am having A LOT of trouble with Geometry right now. I have no idea how to find the area of a regular polygon, like a pentagon or hexagon, when given only the apothem. Please explain how to go about working out these problems. PLEASE don’t use trigonometry. I haven’t even learned trig yet! I just need to know how to do this with a Geometry formula.
Suggestion by Polyhymnio
A = 1/2Pa where P is the perimeter. You cannot find the length of a side or the perimeter without using trig. Sorry!
What do you think? Answer below!
ACT Test question what do I need to study?
I am taking the act in two weeks and have reviewed Algebra and Geometry formulas and grammatical rules. Is there anything else I should look over? What should I get ready the night before?
Suggestion by august
The most important thing is practice test. Make sure you take some and make sure you check the answers you get wrong on the practice test and understand why you got them wrong. Before the ACT you should get a good amount of sleep and eat a good breakfast. It may not seem like it will help but it will. Also for the ACT make sure you bring a calculator, preferably a graphing calculator, and many extra pencils with erasers.
Know better? Leave your own answer in the comments!
What do you need to known before you take geometry?
I’ve taken Algebra I and I will take geometry this summer at a camp. I remember most stuff from Algebra I but graphing is my weakest thing. What do I need to know before taking geometry? Any formulas or concepts might be helpful! thanks a bunch!!
Suggestion by Nomix
There are tons of formulas depending on what you’re doing. If you wanted to practice for it, there’s tons of geometry sites that can help, but for what you’re doing the teacher should inform you of the formula to complete the problems.
Suggestion by nozar nazari
From algebra,you must unserstand that from a point
there can be only and only one prependicular line
and only one parallel line to another line.
good luck and God bless you.
I am a geometry lover.
Suggestion by A H
Know how to solve linear and quadratic equations like 4x + 3 = 9x – 2 and x^2 – 2x + 5 = 0.
Know how to graph a line like y = -x/4 + 3.
Know the various forms of a line, particularly slope-intercept and point-slope.
Know how to solve a system of equations: two equations and two variables, like x + 4 = 2y and -6x = 5y + 9.
Know three major methods to do the above: Substitution, elimination, and graphing both lines.
Know how to recognise when two equations in x and y are parallel, and when they represent the same line. Know that these situations represent “no solution” and “infinitely many solutoins”, respectively.
Know the quadratic formula. You may not need it directly in geometry, but you’ll DEFINITELY need it for Algebra 2.
Know how to find the areas of basic shapes: rectangles, squares, right triangles, and possibly parallelograms. You may know these from algebra; you’ll prove the formulas for them, and learn a few more area formulae.
Know your basic properties of algebra:
1) Associative property: a + (b + c) = (a + b) + c or (ab)c = a(bc)
2) Commutative property: a + b = b + a, ab = ba
3) Distributive property: a(b + c) = ab + ac
Understand the groupings of numbers: Positive integers, zero, negative integers, nonnegative integers, rational numbers, irrational numbers, and real numbers.
Know how to FOIL binomials, or multiply slightly bigger stuff like (a+b+c)(x+y).
Know how to simplify a radical like 1 / SQRT(2) or SQRT(48).
Know the pythagorean theorem a^2 + b^2 = c^2. You’ll probably come upon this formula quickly in geometry as the “distance formula” between two coordinates (x1, y1) and (x2, y2), which is D^2 = (y2 – y1)^2 + (x2 – x1)^2
Know the basic inequality x^2 >= 0. This means the square of any quantity must be nonnegative. Know what that means, and be able to readily identify the minimum value of quantities like (x-3)^2 + 3 or (x-6)^2. Be able to complete the square.
Give your answer to this question below!
Algebra2go Beginning Algebra Video Series.