1.) In solving the equation (x + 1)(x - 2) = 4, Eric stated that the solution would be x + 1 = 4 => x = 3 or (x - 2) = 4 => x = 6. However, at least one of these solutions fails to work when substituted back into the original equation. Why is that? Please help Eric to understand better; solve the problem yourself, and explain your reasoning.

2.) If a stone is tossed from the top of a 330 meter building, the height of the stone as a function of time is given by h(t) = -9.8t2 - 10t + 330, where t is in seconds, and height is in meters. After how many seconds will the stone hit the ground? Round to the nearest hundredth's place; include units in your answer.

3.) Use the discriminant to determine whether the following equations have solutions that are: two different rational solutions; two different irrational solutions; exactly one rational solution; or two different imaginary solutions.
3x^2 + 6x - 5 = 0

Solution Preview

1. Eric should be making use of the Zero Product Theorem, but for that to work the product of his two factors must be 0. Here is the correct solution.

x^2 - x ...

Solution Summary

The expert solves an equation. The nearest hundredths place are provided.

1. Complex Exponentials: Simply the following expression and give your answer both in polar and rectangular form.
o c=3ejπ/4+4e−jπ/2
2. Difference Equations: Solve the following difference equation using recursion by hand (for n=0 to n=4)
o y[n] + 0.5y[n-1] = 2x[n-1]; x[n] = δ[n], y[-1] = 0
3. Differential Equations

How does solving an equation differ from manipulating an expression? How are they alike?
Very few situations in the real world fit a linear pattern or even a non-linear pattern perfectly. How can we tell if the algebraic model we are using fits the situation "good enough?"

Dear TA,
Please be kind to show me how to factor following equation. Find solution for x. The answer is x=2. I try to factor out an x but that doesn't work and I don't think using the quadratic equation would work either. Also, I try factoring out in pairs but that doesn't work either. Thank you in advance.
Y=X+6
Y=X^3
X

(see attached for full problem description)
(a) Use the quadratic formula to determine, to the nearest tenth, the roots of theequation:
2x^2 + 1 = -4x.
(b) Determine the vertex of the parabola y = 2x^2 + 4x + 1. (recall the x value of the vertex is given by x = -b/2a)
(c) Use parts a and b to sketch the grap

A google search has left me still confused as to what the "right" residual income equation is: http://swoba.hhs.se/hastba/abs/hastba1999_010.htm
Help please: kindly write all the CALCULATIONS IN an EXCEL SPREADSHEET, so I can follow and better understand exactly what goes into a firm price's calcuation and a residual income c

Explain the four steps used in solvingthe quadratic equation
Given a quadratic equation: ax ² + bx + c
Solve theequation for zero by factoring.
Four Steps to solve by factoring using the following example
y=x2 + 2x + 1, note; a=1, b=2, and c=1