please solve this
x^2-2x-15?
I know the answer is (x-5)(x+3)
But what are the steps to get this answer?
another problem I am not sure about
12a^5b/18a^3b^6
I know or think the answer is 2a^2/3b^5
if thats right what are the steps in between to get that answer?
ranjankar
Favorite Answer
x^2 -2x -15
x^2 +3x -5x -15
x ( x+3) -5( x+3)
( x-5) ( x+3) ANSWER
2) 2a^2/3b^5 ANSWER
?
x² - 2x – 15 = 0
a = 1, b = -2 and c = -15
you can use the
- factoring
- Completing the perfect square root
- Square root
by factoring
(1/a)(ax + P)(ax + Q) = 0
(1/1)(1x + P)(1x + Q) = 0
(x + P)(x + Q) = 0
P + Q = b = -2
PQ = a*c = 1 * -15 = -15
who meet for the P and Q
P = -5 and Q = 3
Because
P+Q = -5 + 3 = -2
PQ = (-5)(3) = -15
Then
(x – 5)(x + 3) = 0
Moon
x^2-2x-15?
you probably mean to factor this?
x^2-2x-15
=x^2 - 5x + 3x - 15
= (x+3)*(x-5) ................................... answer
12a^5b/18a^3b^6
you mean to simplify this?
12a^5b/18a^3b^6
= (2 * 6 * a^5 * b) / (3 * 6 * a^3 * b^ 6)
........... strike out the commons for 1
= (2 * 1 * a^2 * 1) / (3 * 1 * 1 * b^5)
............ combine
= 2 a^2 / 3 b^5 .......... answer
Anonymous
1. look up factoring. Once you learn it, here is my answer- -15=-5*3, which when added together equal -2, so it works out by factoring. You can check it by multiplying (x-5) by (x+3) and getting x^2-2x-15.