Answer:
Divide both sides by 3.
(x+2)^2=16
Square root both sides.
x+2= ± 4 (plus OR minus, can be either so we have to include both)
Minus 2 from both sides.
x=-2 ± 4
Add and minus the 4 to -2.
x = -2-4 = -6 and x=-2+4 = 2
Step-by-step explanation:
First find the factors of 100 then
y2 + 20y +100
y2 +10y + 10y +100
y ( y + 10) + 10(y + 10)
So the factor is ( y + 10)
Option C is the correct answer
Answer:
20, 4
Step-by-step explanation:
Let's assume total number of students registered is n
Last week n/4 people are absent
so people present are n - n/4 = <u>3n/4</u>
Today after return of Jen 1/5 n are absent
so people present are n - n/5 = 4n/5
which is also equal to last week present people + 1 (Jen)
= 3n/4 + 1
= (3n + 4) / 4
so (3n + 4) / 4 = 4n/5
=> 3n + 4 = 4n/5 * 4
=> (3n + 4) * 5 = 16n
=> 15n + 20 = 16n
=> 20 = n
=> n = 20
So total students registered for class is 20
today no of people absent = n/5 = 20/5 = 4
Answer:
No they don't form a proportion
Step-by-step explanation:
Their denominatiors do not share a common multiple, therefore they can not form a proportion.
Let
x------> the length side of the square base of the box
y-------> the height of the box
we know that
volume of the box=b²*h
b=x
h=y
volume=256 cm³
so
256=x²*y------>y=256/x²--------> equation 1
<span>The amount of material used is directly proportional to the surface area, so we will minimize the amount of material by minimizing the surface area.</span>
surface area of the cardboard=area of the base+perimeter of base*height
area of the base=x²
perimeter of the base=4*x
height=y
surface area=x²+4x*y-----> equation 2
substitute equation 1 in equation 2
SA=x²+4x*[256/x²]-----> SA=x²+1024/x
step 1
find the first derivative of SA and equate to zero
2x+1024*(-1)/x²=0------> 2x=1024/x²----> x³=512--------> x=8 cm
y=256/x²------> y=256/8²-----> y=4 cm
the answer is
the length side of the square base of the box is 8 cm
the height of the box is 4 cm
