math

Here's my question: Determine if each system has one, two, or no solutions. (Show your work - 3 marks each)

a)y=2x^2-2x+1 and y=3x-5

b)y=x^2+3x-16 and y=-x^2-8x-18

Here's my work on the question:

a)

x=(-b plus/minus sign (square root b^2-4ac)/(2a)
x=(--2 plus/minus sign (square root -2^2-4(2)(1)/(2(2)
x=(2 plus/minus sign (square root -4-8)/(4)
x=( 2 plus/minus sign (non-real answer)/(4)

x=(-b plus/minus sign (square root b^2-4ac)/(2a)
x=(--5 plus/minus sign (square root -5^2-4(3)/2(3)
x=(5 plus/minus sign(square root -25-12)/6
x=(5 plus/minus sign(square root -37)/6

b)
x=(-b plus/minus sign (square root b^2-4ac)/(2a)
x=(-3 plus/minus sign (square root 3^2-4(1)(-16)/(2(1))
x=(-3 plus/minus sign (square root 9--64)/2
x=(-3 plus/minus sign (square root 73)/2
x=(-3 plus/minus sign (8.54)/(2)
x=4.27

x=(-b plus/minus sign (square root b^2-4ac)/(2a)
x=(--8 plus/minus sign(square root -8^2-4(-1)(-18)/(2(-1)
x=(8 plus/minus sign(square root-64-72)/(-2)
x=(8 plus/minus sign(square root -136)/(-2)

1. first, do a google on special characters to find the ±√ symbols, which you can then copy and paste. All those words are just too ugly for words! You have

y=2x^2-2x+1 and y=3x-5, so set them equal:

2x^2-2x+1 = 3x-5
2x^2-5x+6 = 0

The discriminant (b^2-4ac) is negative, so there are no solutions.

For the other,

y=x^2+3x-16 and y=-x^2-8x-18

x^2+3x-16 = -x^2-8x-18
2x^2+11x+2 = 0

the discriminant is positive, so it has two distinct solutions.

See the graphs at

http://www.wolframalpha.com/input/?i=plot+y%3D2x^2-2x%2B1+%2C+y%3D+3x-5

http://www.wolframalpha.com/input/?i=plot+y%3Dx^2%2B3x-16+%2C+y%3D-x^2-8x-18

posted by Steve

First Name

Similar Questions

1. algerbra

could you please double check my work question:find the roots of the equation 2x^2+8x=12 by completing the square. leave answer in simplest radical form. work and answer: c=(b/2)^2 c(4/2)^2=4 2x^2 +8x=12 divide everything by 2 x^2
2. math

Determine if each system has one, two, or no solutions. (Show your work - 3 marks each) a)y=2x^2-2x+1 and y=3x-5 b)y=x^2+3x-16 and y=-x^2-8x-18
3. math

Determine if each system has one, two, or no solutions. (Show your work - 3 marks each) a)y=2x^2-2x+1 and y=3x-5 b)y=x^2+3x-16 and y=-x^2-8x-18
4. math

Nakim simplified 3 times the square root of 2x plus x times the square root of 8x minus 5 times the square root of 18x and got -10x times the square root of 2x for an answer. Part 1: Using complete sentences, explain what Nakim
5. College Algebra

I need some help with a handful of questions. I need to see the steps on how to get to the final answers. I would also appreciate if you can explain how you got to those steps. Rationalize each expression by building perfect nth

I need some help with a handful of questions. I need to see the steps on how to get to the final answers. I would also appreciate if you can explain how you got to those steps. Rationalize each expression by building perfect nth
7. College Algebra

I need some help with a handful of questions. I need to see the steps on how to get to the final answers. I would also appreciate if you can explain how you got to those steps. Rationalize each expression by building perfect nth
8. @someone who can show me how to do this

Hi I'm Aluminum<3 Helping and C.S.I, but you can call me Alumi. for short. So here's my Question,Determine how many solutions exist for the system of equations. I need someone who can WORK IT OUT with me and SHOW me how to do
9. MATH

how do you simplify square root of 27 minus square root of 49 all divided by square root of 3. I have gotten two different answers when I tried to check it. It kind of looks like (27-49) (3) except all the numbers have their own
10. mat115

Please help me with this math question. I am asked to show my work but I don't know how to solve the problem to show my work. The question is: Choose the correct list of factors of the number 8. Again, I have to show my work with

More Similar Questions