Are you familiar with z-scores? According to the definition,
(given numerical value) - (mean)
z = ---------------------------------------------
standard deviation
Thus, with the given numerical value equal to 410 and the std. dev. equal to 75, the corresponding z-score is
410-500 -90
z = --------------------- = --------------- = -1.2
75 75
Use a table of z-scores to determine the area under the standard normal curve to the left of z = -1.2. Your result is the probability that a given family chosen at random spends less than $410 per month.
Answer:
f(x) = 2(x –3)²
Step-by-step explanation:
f(x) = 2x² – 12x + 18
The vertex form of the above expression can be obtained as follow:
f(x) = 2x² – 12x + 18
Factorise
f(x) = 2(x² – 6x + 9)
Next, we shall simplify x² – 6x + 9 by factorisation method.
This is illustrated below:
x² – 6x + 9
Multiply the first term i.e x² and last term i.e 9 together. The result is 9x².
Next, find two factors of 9x² such that their sum will result to the 2nd term i.e –6x in the expression above.
The factors are –3x and –3x
Next, replace –6x with –3x and –3x in the equation above as shown below:
x² – 6x + 9
x² – 3x –3x + 9
Factorise
x(x – 3) –3(x –3)
(x –3)(x –3)
(x –3)²
f(x) = 2x² – 12x + 18
f(x) = 2(x² – 6x + 9)
f(x) = 2(x –3)²
Therefore, the vertex form of the function f(x) = 2x² – 12x + 18 is
f(x) = 2(x –3)²
Answer:
x = 9
y = 12
Step-by-step explanation:
✔️m<ADB = 90°
7x + 27 = 90
7x = 90 - 27
7x = 63
Divide both sides by 7
x = 9
✔️BC = 2(BD)
3y - 7 = 2(y + 3)
3y - 7 = 2y + 6
Collect like terms
3y - 2y = 7 + 6
y = 12
