Answer:
Step-by-step explanation:
The equation of a straight line can be represented in the slope intercept form as
y = mx + c
Where
m = slope = (change in the value of y in the y axis) / (change in the value of x in the x axis)
The equation of the given line is
x + 2y = 4
2y = - x + 4
y = -x/2 + 4/2
y = - x/2 + 2
Comparing with the slope intercept form, slope = - 1/2
If two lines are perpendicular, it means that the slope of one line is the negative reciprocal of the slope of the given line.
Therefore, the slope of the line passing through (- 2, 1) is 2
To determine the intercept, we would substitute m = 2, x = - 2 and y = 1 into y = mx + c. It becomes
1 = 2 × - 2 + c = - 4 + c
c = 1 + 4 = 5
The equation becomes
y = 2x + 5
Answer:
7.065 sq. cm
Step-by-step explanation:
Diameter= 3 cm
Since 2r=d, the radius is 1.5 cm
Circle area formula:
πr^2 --> 3.14(r^2)
Plug in r:
A=3.14(1.5^2)
A=3.14(2.25)
A=7.065
Answer: 1.25
Step-by-step explanation:
Given: A college-entrance exam is designed so that scores are normally distributed with a mean
= 500 and a standard deviation
= 100.
A z-score measures how many standard deviations a given measurement deviates from the mean.
Let Y be a random variable that denotes the scores in the exam.
Formula for z-score = 
Z-score = 
⇒ Z-score = 
⇒Z-score =1.25
Therefore , the required z-score = 1.25
The radius times pie equals the circumference. keep that in mind
Answer:
B
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
To obtain this form use the method of completing the square
Given
x² - 8x + y² - 2y - 8 = 0 ( add 8 to both sides )
x² - 8x + y² - 2y = 8
add ( half the coefficient of the x/y terms )² to both sides
x² + 2(- 4)x + 16 + y² + 2(- 1)y + 1 = 8 + 16 + 1
(x - 4)² + (y - 1)² = 25 → B
