SOLUTION: Could you tell me please if these are correct. 1. root12((-10))^12 Answer N not a real number 2. Use the foil method to find the product (9x^8-7)(x^9-5)= Answer 9x^17-7x9-45x^

Algebra ->  Rational-functions -> SOLUTION: Could you tell me please if these are correct. 1. root12((-10))^12 Answer N not a real number 2. Use the foil method to find the product (9x^8-7)(x^9-5)= Answer 9x^17-7x9-45x^      Log On


   



Question 198236: Could you tell me please if these are correct.
1. root12((-10))^12
Answer N not a real number
2. Use the foil method to find the product
(9x^8-7)(x^9-5)=
Answer 9x^17-7x9-45x^8+35
3. For the following equation state the value of the disctiminant and then describle the nature of the solution
12x^2-8x+7=0
Answer -272
4. Factor
a^2+6a+9=
Answer (a+3)^2

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
# 1

Is the expression root%2812%2C%28-10%29%5E12%29??? If so, then root%2812%2C%28-10%29%5E12%29=10


On the other hand, if the expression is %28root%2812%2C-10%29%29%5E12, then result is NOT a real number. Why? You CANNOT take an even root of a negative number and get a real number (eg you can't take the square root of -2).




# 2

You are correct. %289x%5E8-7%29%2A%28x%5E9-5%29=9x%5E17-7x%5E9-45x%5E8%2B35





# 3




From 12x%5E2-8x%2B7 we can see that a=12, b=-8, and c=7


D=b%5E2-4ac Start with the discriminant formula.


D=%28-8%29%5E2-4%2812%29%287%29 Plug in a=12, b=-8, and c=7


D=64-4%2812%29%287%29 Square -8 to get 64


D=64-336 Multiply 4%2812%29%287%29 to get %2848%29%287%29=336


D=-272 Subtract 336 from 64 to get -272


Since the discriminant is less than zero, this means that there are two complex solutions.


In other words, there are no real solutions.


You got the right discriminant value, but you forgot to mention what that meant in terms of the number of solutions.





# 4

You are correct, a%5E2%2B6a%2B9 factors to %28a%2B3%29%5E2.


You can verify the answer by

a) Graphing a%5E2%2B6a%2B9 and %28a%2B3%29%5E2 on the same grid. You'll see that they are the same graph, or...

b) You can FOIL %28a%2B3%29%5E2 to get a%5E2%2B6a%2B9