College Algebra
posted by Kristen .
I have a few problems I need help with and also do have multiple choice. If I can have an explanation of how to get the answer that would be great.
1. Use the discriminant to determine whether the given equation has two irrational roots, two rational roots, one repeated root, or two complex roots.
x^24x=5
a.) Two rational roots
b.) one repreated root
c.) two complex roots
d.) two irrational roots.
2.Use the discriminant to determine whether the given equation has two irrational roots, two rational roots, one repeated root, or two complex roots.
3x^3+19x20=0
a.) Two rational roots
b.) one repreated root
c.) two complex roots
d.) two irrational roots.
3. Use the discriminant to determine whether the given equation has two irrational roots, two rational roots, one repeated root, or two complex roots.
5x^27x5=0
a.) Two rational roots
b.) one repreated root
c.) two complex roots
d.) two irrational roots.
4. Use the discriminant to determine whether the given equation has two irrational roots, two rational roots, one repeated root, or two complex roots
x^212=7x
a.) Two rational roots
b.) one repreated root
c.) two complex roots
d.) two irrational roots.

All these are based on the following concept (should be in your text)
for ax^2 + bx + c = 0
if b^2  4ac < 0 there are two imaginary or complex roots
if b^2  4ac = 0 , there is one root, (one repeated root)
if b^2  4ac > 0 , there are two distinct and real roots
if for the last case, b^2  4ac is a perfect square, then the two real roots will be rational, otherwise they are irrational.
in each case, evaluate b^2  4ac and decide where it fits in
remember to arrange the equation in the proper form
I will do #4
x^2  12 = 7x
x^2  7x  12 = 0 , a=1, b=7 , c= 12
b^2  4ac
= 49  4(1)(12) = +97
so we will have 2 irrational roots
Respond to this Question
Similar Questions

Excel
I have to create a payroll document for class using Excel and I am quite confused. Here is the parts that I am confused on. I have to calculate the number of years the employees have been working for us, I believe the function I need … 
algebra
What would be the discriminant for this equation: x^22x+12=0 How many solutions are there? 
History
Hi I need some help with my history homework I have answer all of the question I just need help with a few about the Sumerian civilization. I just want to get some idea so that I can research these topics better. 1.Type of Governmen … 
physics
Hi, my teacher doesn't teach us too well and we have a few packets to hand in for tomorrow that I really don't understand much of. If someone could give me the answers to all of the problems on the first link if you search "the electrical … 
College Algebra
I need some help with a few problems. They are multiple choice but need a breakdown on how I can work the problems. Thanks for your help! 1. Factor the trinomial completely. 10x^2 + 11x6 a. (2x+3)(5x2) b. (2x3)(5x+2) c. (10x+3)(x2) … 
College Algebra
I have a few more questions that I'm not understanding. Its multiple choice however I would appreciate a breakdown on how to solve. 1.Evaluate without a calculator, using the order of operations. 2^2+20820squareroot of 64 a. … 
College Algebra
I have a few more questions that I'm not understanding. Its multiple choice however I would appreciate a breakdown on how to solve. 4.Simplify the compound rational expression. Use either method. 1+(5/y10)/y+(25/y10) a. 1/y5 b. … 
College AlgebraStill Confused
I have a few problems I need help with and also do have multiple choice. If I can have an explanation of how to get the answer that would be great. 1. Use the discriminant to determine whether the given equation has two irrational … 
math
kx^2 + (k+2)x 3 =0 has roots which are real and positive. Find the possible values that k may have. I understand that I have to use the discriminant to solve this, but I can't seem to get the answer right, so I really need help!! 
Algebra
Determine the discriminant for the quadratic equation 3 = x^2 + 4x + 1. Based on the discriminant value, how many real number solution does the equation have?