Please not the ?^? means the number following it is an exponent. For example x^2 means x squared.
1. Find the roots of the following equation by factoring.
x^2 + x - 12 = 0
2. Find the roots of the following equation by factoring.
2x^2 + 13 x = - 15
3. Find the quadratic equation that has the roots: 7, - 3
4. Find the quadratic equation that has the roots: - 1/3, -2
5. Find the roots of the following equation by completing the square
x^2 + 7x = 8
6. Find the roots of the following equation
2x^2 - 24 = 8x
7. True or false? The quadratic formula can be used to find the roots of any quadratic equation.
8. Find the roots of: x^2 - 16 = 0
9. Find the axis of symmetry and the roots for the following equation:
y = x^2 - 10x + 25
10. Find the axis of symmetry and the roots for the following equation:
Y = x^2 - 10x + 16
2006-07-18 08:42:10 · 5 answers · asked by Anonymous in Education & Reference ➔ Homework Help
do ur own homework,lazy bum!!!! look in the back of the book!!!
2006-07-18 08:47:47 · answer #1 · answered by Anonymous · 1⤊ 1⤋
x^2 + x - 12 = 0
factors of 12 are 1 and 12; 3 and 4; 2 and 6
factors that can subtract (look at the sign in front of the 12) and get 1 are 3 and 4
6-2 or 2-6 does not equal 1, nor does 1 and 12
therefore (x 3)(x 4)
multiplied, they must get a -
which means that one of the numbers is negative
and added, they must get 1, which means that the 4 has to be positive and the 3 negative
so (x-3)(x+4)
therefore, x = 3, and x = -4 b/c the eq is set up so that (x-#)
2x^2 + 13 x = - 15
2x^2 + 13 x + 15 = 0
factors of 15 are 1 and 15; 3 and 5
one of the factors has to be multiplied by 2 (in front of the x^2) and the sum of the two (look at sign before the 15) has to be 13
3 + 2*5 = 13
so (2x+3)(x+5)
x = 7, -3
(x-7)(x+3)
x^2 + -7x + 3x + -21
x^2 - 4x - 21
same as before
i don't really remember completing the square
i get (x+6)(x+1)=6 look at above examples
but i don't know what to do from there
look at above examples
true
x=4, -4
when you have a^2-b^2, the answer is always (a+b)(a-b)
see before examples
see before examples
2006-07-18 09:05:26 · answer #2 · answered by mommy_mommy_crappypants 4 · 0⤊ 0⤋
x^2 + x -12
= x^2 +4x-3x-12
=x(x+4)-3(x+4)
= (x+4)(x-3)
similarly try rest of the questions.
2006-07-18 08:49:55 · answer #3 · answered by flori 4 · 0⤊ 0⤋
7. True
2006-07-18 08:46:01 · answer #4 · answered by fcas80 7 · 0⤊ 0⤋
whoa u got work girl fell sorry for u!!!
2006-07-18 08:47:32 · answer #5 · answered by the girl 2 · 0⤊ 0⤋