Answer:
3a. 84
3b. 150
Step-by-step explanation:
(3*7)+(3*21)
what is 3*7? it's 21
what is 3*21? it's 63
so 21 + 63 is the answer to the first question :D
10*(8+7)
8+7 first cause it's in parentheses
15
10*15 is equal to 150
Step-by-step explanation:
b^2-4b+3=0
b²-3x-b+3=0
b(b-3)-1(b-3)=0
(b-3)(b-1)=0
either
b=3 or b=1
.
2n^2 + 7 = -4n + 5
2n²+4n+7-5=0
2n²+4n+2=0
2(n²+2n+1)=0
(n+1)²=0/2
:.n=-1
.
x - 3x^2 = 5+ 2x - x^2
0=5+ 2x - x^2-x +3x^2
0=5+x+2x²
2x²+x+5=0
comparing above equation with ax²+bx +c we get
a=2
b=1
c=5
x={-b±√(b²-4ac)}/2a ={-1±√(1²-4×2×5)}/2×1
={-1±√-39}/2
Answer:
P(x < 5) = 0.70
Step-by-step explanation:
Note: The area under a probability "curve" must be = to 1.
Finding the sub-area representing x < 5 immediately yields the desired probability.
Draw a dashed, vertical line through x = 5. The resulting area, on the left, is a trapezoid. The area of a trapezoid is equal to:
(average length)·(width, which here is:
2 + 5
----------- · 0.02 = (7/2)(0.2) = 0.70
2
Thus, P(x < 5) = 0.70
Answer:
The area of the shaded portion of the figure is
Step-by-step explanation:
see the attached figure to better understand the problem
we know that
The shaded area is equal to the area of the square less the area not shaded.
There are 4 "not shaded" regions.
step 1
Find the area of square ABCD
The area of square is equal to

where
b is the length side of the square
we have

substitute

step 2
We can find the area of 2 "not shaded" regions by calculating the area of the square less two semi-circles (one circle):
The area of circle is equal to

The diameter of the circle is equal to the length side of the square
so
---> radius is half the diameter
substitute


Therefore, the area of 2 "not-shaded" regions is:

and the area of 4 "not-shaded" regions is:

step 3
Find the area of the shaded region
Remember that the area of the shaded region is the area of the square less 4 "not shaded" regions:
so
---> exact value
assume

substitute