Answer: B) f(x)= 1/5 |x|
Used graphic calculator
<span>3,-6,12,-24,48,-96,192,-384,768,-1536
sum:
</span>3 -6+12 -24+ 48 -96+ 192 -384+ 768 -1536 = -1023
Answer is C. -1023
Step-by-step explanation:
they're is a neat little trick.
but first of all, "roots" means the 0 solutions of the equation. like
ax² + bx + c = 0
there are 2 solutions for x to make the whole expression equal 0.
these are the "roots".
now to the little trick :
when is a multiplication resulting in 0 ?
when at least one of the factors is 0.
and any quadratic expression can be written as multiplication of 2 factors. like
c(x - a)(x - b) = cx² - cax - cbx + cab
what are the "roots" or 0 points ?
either
c = 0
x - a = 0 | x = a
x - b = 0 | x = b
the leading coefficient = 3.
that means nothing else than c = 3.
root = 1 means (x - 1) is one factor.
root = -5 means (x + 5) is the other factor.
so, we have
3(x - 1)(x + 5) = 3x² + 12x - 15
and the equation is
3x² + 12x - 15 = 0
or
3x² + 12x = 15
9514 1404 393
Answer:
x = 7 1/3
Step-by-step explanation:
The smaller triangle is 6/9 = 2/3 the size of the larger triangle, so the left side is ...
(x -2) = (2/3)(8)
3(x -2) = 16 . . . . . multiply by 3 to clear fractions
3x -6 = 16 . . . . . . eliminate parentheses
3x = 22 . . . . . . . . add 6; next divide by 3*
x = 22/3 = 7 1/3 . . . . . feet
_____
* Note that we multiplied by 3, then divided by 3. If you're comfortable working with fractions and/or mixed numbers, these steps are unnecessary. The answer is simply x = 2 + 16/3 = 22/3.
Marco rounded the hundredths place since after the decimal it is the tenths then the hundredths then the thousands place
