- Wed Mar 04, 2015 3:47 am
- Forum: Intermediate Algebra
- Topic: help with a few problems
- Replies:
**1** - Views:
**93**

some problems I need due before 12. need help! 1.graph by plotting: -7x+3y=-21 they show how to graph here: http://www.purplemath.com/modules/graphlin.htm 3.find the equation of line through (11,4) perpendicular to y = -8 they explain line eqns here: http://www.purplemath.com/modules/strtlneq.htm 4...

- Thu Feb 19, 2015 9:42 pm
- Forum: Intermediate Algebra
- Topic: Finding the size foundation that takes up all sidings of a tool shed
- Replies:
**1** - Views:
**154**

Shawn is building a tool shed with a square foundation and has enough siding to cover 20 linear feet of walls If he leaves a 4-foot space for a door, then what size foundation would use up all his siding? Not sure how to approach this problem. A formula would also be nice. try using the formulas fo...

- Tue Feb 03, 2015 2:00 pm
- Forum: Trigonometry
- Topic: Trig help! 5cosx - 4sin^2x =2 w/o Pythagorean identities
- Replies:
**1** - Views:
**255**

I was wondering if anyone could help me with an extension trig question that we've been given as homework. We've not been taught Pythagorean identities yet. -360<x<360 5cosx - 4sin^2x =2 R U supposed to solve? if U cant use "cos^2 + sin^2 = 1" then i'm not sure how Ur supposed to do this?...

- Mon Jan 12, 2015 6:24 pm
- Forum: Advanced Algebra ("pre-calculus")
- Topic: Difficult question
- Replies:
**7** - Views:
**681**

i'm still stuck with the same situation where I have 0=16t^2-144t+180 and I cant get it simplified enough to solve for t. the best I'm able to break it down to is 4t^2-36t+45 which is where I get stuck. put the "=0" back in & solve the quad: http://www.purplemath.com/modules/solvquad....

- Mon Dec 01, 2014 1:55 pm
- Forum: Forum Rules & Guides
- Topic: Pasting an image in a Post
- Replies:
**4** - Views:
**2509**

That didn't seem to work for images stored on Google Drive. maybe google drive doesnt allow hotlinking?? try putting the image somewhere else & then link like they say here: http://www.purplemath.com/learning/faq.php#f3r3 heres a linked image: http://www.purplemath.com/modules/matrices/hand_ani...

- Tue Nov 18, 2014 2:47 am
- Forum: Intermediate Algebra
- Topic: Relationship between a square and a parabola?
- Replies:
**3** - Views:
**828**

Moriarty wrote:I complete a "square", but when I graph that function the shape is a parabola.

the square Ur completing is (x - h)^2.

the x - h is squared so U have a "square" of a binomial.

its the power not the shape.

- Tue Nov 11, 2014 12:23 am
- Forum: Beginning Algebra
- Topic: Simplifing radicals
- Replies:
**3** - Views:
**730**

K_V8 wrote:(sqrt(16 - 64)) / 2

(sqrt(-48)) / 2

(sqrt(-4*12)) / 2

4i(sqrt(12)) / 2

how are U getting that sqrt[4] = 4??

to learn how roots work, try here: http://www.purplemath.com/modules/radicals.htm

then start w/ sqrt[4*4*(-3)]

- Mon Nov 10, 2014 6:24 pm
- Forum: Intermediate Algebra
- Topic: Sum or Difference of Cubes
- Replies:
**1** - Views:
**490**

how would you solve this: x^3 -1000 = 0 I Did this: changed it to: (x-1,000)(x^2-1,000x - 1,000,000) the formula is wrong and the numbers Ur putting in the formula are wrong U have to have a^3 - b^3 = (a - b)(a^2 + ab + b^2) Ur doing a^3 - b = (a - b)(a^2 - ab - b^2) Now we know x = 1000. how? if x...

- Mon Nov 10, 2014 6:18 pm
- Forum: Beginning Algebra
- Topic: Simplifing radicals
- Replies:
**3** - Views:
**730**

How do you simplify this radicals number: (sqrt(16 - 64)) / 2 (Do I divide first? Subtract first? Simplify using imaginary numbers first?) do the order of operations: http://www.purplemath.com/modules/orderops.htm the most outside thing is the "divide by 2" then Ur next thing is the "...

- Sun Nov 02, 2014 11:53 pm
- Forum: Trigonometry
- Topic: Graphing Trigonometric functions
- Replies:
**1** - Views:
**806**

How would you graph the function Y=1/2 Tan(x+Pi/2) for 2 periods. Could you please specify the asymptotes as well. Thanks they show how to do that here: http://www.purplemath.com/modules/grphtrig.htm because x isn't multiplied by anything, the period is the regular length so the asymptotes are the ...