- Thu Feb 10, 2011 4:35 am
- Forum: Beginning Algebra
- Topic: which answer? is f(4) for f(x)=-x**2+5x-7 equal to 29 or -3?
- Replies:
**1** - Views:
**1594**

Given : f(x) = - x**2+5x-7 notice the - before the first term. This is ambiguous. It is a homework problem. what is the value of f(4)? is it 29 or -3 ? The answer is -3. Here is why: You function is f(x)=-x^2+5x-7 this makes f(4)=-(4)^2+5(4)-7=-16+20-7=-3 In other words the negative is not part of ...

- Sun Feb 06, 2011 4:18 pm
- Forum: Intermediate Algebra
- Topic: Intercepts 1: how to find where y = x2 + 3x + 2 crosses?
- Replies:
**1** - Views:
**1190**

To find out where the graph crosses the x axis you must find those values of x that, when put into the equation, make y equal to zero.

This can be done by factoring the quadratic expression. Learn how here.

SD

This can be done by factoring the quadratic expression. Learn how here.

SD

- Sun Feb 06, 2011 1:33 am
- Forum: Intermediate Algebra
- Topic: finding the function? trig problem
- Replies:
**1** - Views:
**1743**

find the function : d) f(-x) equation : 2x+1/3x-5 answer: 2x-1/3x-5 second equation: e) -f(x) equation : 2x+1/3x-5 answer: -2x-1/3x-5 I ONLY NEED THE WORK ! Your answer to "d" is incorrect: the answer is \frac {-2x+1} {-3x-5} What f(-x) means is wherever you see an "x" in the original equation put ...

- Sun Feb 06, 2011 1:25 am
- Forum: Beginning Algebra
- Topic: Factoring Trinomials: x^2 - 4x - 4, 2x^3 - 8x^2 + 2x
- Replies:
**1** - Views:
**1825**

Hi Everyone! I'm helping my little brother with his math homework, and it's been a long time since I did this. I'm really stumped on these two and would love some fresh eyes. TIA Nita Factor the following trinomials. 1.x^2 –4x – 4 2.2x^3 - 8x^2 + 2x You can learn about factoring quadratic expressio...

- Sun Feb 06, 2011 1:21 am
- Forum: Intermediate Algebra
- Topic: solve x^3-x^2+25x-25=0 for x; find poly w/ given zeroes
- Replies:
**2** - Views:
**1829**

Solve for x: x^3-x^2+25x-25=0 ...... my question is where do i study the material necessary for learning how to solve for x? Math Word Problem: Sketch a graph and write an equation for a polynomial of least degree with integer coefficients that has the given zero a) 0,2, -3 b) 3 (multiplicity 2) an...

- Sun Jan 30, 2011 9:00 pm
- Forum: Intermediate Algebra
- Topic: Linear functions and arithmetic series..
- Replies:
**1** - Views:
**1384**

Hi, The text asks the following. For context, the book has been discussing the arithmetic sequence for the last several pages, so the a_n refers to a_n=a_1 + (n-1)d : For the linear function y=mx+b , y=a_n and x = n . Express a_1 and d of the arithmetic sequence in terms of m and b . I sort of just...

- Wed Jan 26, 2011 8:26 pm
- Forum: Pre-Algebra
- Topic: Describe graph of interval [-4, 10]
- Replies:
**2** - Views:
**4900**

Please help having a hard time understainding this. Describe what the graph of interval [-4, 10] looks like. Is it a solid dot at -4, a solid dot at 10 and a heavy line that connects to the two. The dots are solid as there is a square bracket at the ends of the interval. :?: You are correct, you wo...

- Tue Jan 25, 2011 11:30 pm
- Forum: Beginning Algebra
- Topic: need linear equation help
- Replies:
**1** - Views:
**1238**

ok, it's been a while since i've done this so i dont remember what i'm doing, if someone could help me that would be awesome :D 2z+7/8-2=z+z-1/2 There is no answer to this question: You have 2z + \frac 7 8 - 2 = z + z - \frac 1 2 Which is 2z + \frac 7 8 - 2= 2z - \frac 1 2 Subtract 2z from both sid...

- Fri Jan 21, 2011 3:31 am
- Forum: Pre-Algebra
- Topic: Name the property that justifies each statement
- Replies:
**3** - Views:
**5285**

I assume this question is part of a larger assignment because your question doesn't have variables. Variables would be letters like x, y etc.

The properties of numbers are explained here.

The properties of numbers are explained here.

- Wed Jan 19, 2011 4:20 am
- Forum: Intermediate Algebra
- Topic: simplify expression 4ab(sqrt2b)-3a(sqrt18b^3)=7ab(sqrt6b)
- Replies:
**4** - Views:
**2717**

To clarify, this was the question Simplify: 4ab sqrt{2b} - 3 sqrt{18 b^3} = 7ab sqrt{6b} And yes, we are simplifying an equation. The first step is: (4ab sqrt{2b} - 3 sqrt{18 b^3})^2 = (7ab sqrt{6b})^2 If you are careful with the algebra, you can eliminate all the radicals. In fact, as long as b is ...