Answer:
x=8
Step-by-step explanation:
2x+9=3x+1
-3 -3
-9 -9
-1x=-8
divide both side by -1.
x=8
This is a combination in which you choose 4 from 10.
The formula is
combinations = 10! / 4! * (10-4)!
combinations = 10! / 4! * 6!
combinations = 10 * 9 * 8 * 7 * 6! / 4! * 6!
combinations = 10 * 9 * 8 * 7 / 4 * 3 * 2
combinations = 10 * 3 * 7
combinations = 210
Source:
http://www.1728.org/combinat.htm
Answer:
a = 1
b = -1
c = -2
Step-by-step explanation:
We reorder the equation in such way that let us see the usual
ax² + bx + c = 0
Then the original quation is:
-2 = - x + x² - 4 ⇒ 0 = 2 - x + x² - 4 ⇒ x² - x - 2 = 0
Now we are able by simply inspection to identify a, b . c comparing our equation with the general equation so :
a = 1
b = -1
c = -2
