Answer:
n = 59
Step-by-step explanation:
I find it easiest to work problems of this kind using a graphing calculator. That way, extraneous solutions can be avoided. It seems to work well to rewrite the problem, so you're looking for a value of n that makes the result zero. Here, that would mean you want ...
... f(n) = √(n+5) -√(n-10) -1
_____
The solution by hand involves eliminating the root symbols. You do that by squaring the equation:
... n +5 -2√((n+5)(n-10)) + n -10 = 1
Now, we isolate the remaining root and square again.
... 2n -6 = 2√((n+5)(n-10)) . . . collect terms, add 2√( ) -1
... n -3 = √(n²-5n-50) . . . . . . . divide by 2
... n² -6n +9 = n² -5n -50 . . . . square both sides
... 59 = n . . . . . . . . . . . . . . . . . add 50 +6n -n²
Answer:
25.2
Step-by-step explanation:
2.1*12=25.2
use a calculator if you're allowed to show work that way, if not a simple way is
2.1*10=21
2.1*11=23.1
2.1*12 is equal to 2.1*10=21 because 2*12=24 and .1*12=1.2
The area of the mirror (v) is 9.5x7.5=71.25 inches
Answer:
no, it cannot
Step-by-step explanation:
a difference of square is: a² - b² = (a - b)(a + b)
looking at the expression (5z+3)(-5z-3), we see that it does not fit the criteria of the breakdown of a perfect square, as (-5z-3) has a negative <em>a</em> term (-5z)
if we FOILed (5z+3)(-5z-3) out, we would get:
-25z² - 30z - 9, which is not a difference of squares