Answer: 162.6cm
Step-by-step explanation:
4 boys have a mean height of 162cm. Their total height will be the average multiplied by the number of boys which will be:
= 162 × 4
= 648cm
A new boy with height of 165cm joined. This means that we now have 5 boys and their total height will be:
= 648cm + 165cm
= 813cm
The new mean height will be:
= Total height / Number of boys
= 813 / 5
= 162.6cm
F(x) = -(x + 8)² - 1
<span>The function (not its graph) decreases on interval [-8, ∞). It is a quadratic function in vertex form. That form makes it easy to pick out the one extremum, where x equals -8. The leading coefficient is negative, so the extremum must be a maximum. The function decreases as x increases from there. </span>
<span>Notice that I include the value -8 in the interval. The function does not have instantaneous decrease at that value, but that is not what it means for a function to be decreasing over an interval. </span>
<span>Let a and b be any two values on [-8, ∞), such that a < b. </span>
<span>-8 ≤ a < b </span>
<span>Then f(a) > f(b). Therefore, function f is decreasing on interval [-8, ∞).</span>
Answer:
Umm, maybe ask your parents? Or maybe just save the money for college.
LOL
53) Vertical angles are congruent, so 
54)
and
are supplementary, so 
55) Because vertical angles are congruent,
. Now, because DR bisects
, this means 
56) This is a geometric sequence where the next term is obtained by multiplying the previous term by -2, so the next two numbers are 16, -32
Answer:
volume left in A is 80ml
Step-by-step explanation:
let original volume in both be x ml
after pouring from A to B
vol in A = x - 120
vol in B = x + 120
now it is given that
vol in B = 4 times vol in A
implies

hence original volume in A is 200ml. after pouring in B it is 200-120 = 80 ml