Answer:
1) 25
2) 2
3) f(g(1)) = 42
Step-by-step explanation:
1) Given that f(x) = 4x^2 + 9
If x = -2
f(-2) = 4(-2)^2 + 9
f(-2) = 4(4) + 9
f(-2) = 16 + 9
f(-2) = 25
2) Given that f(x) = 4x - 6
y = 4x - 6
Replace y with x
x = 4y - 6
MAke y the subject of the forfmula
4y = x+ 6
y = (x+6)/4
SInce x = 2
f^(-1)(2) = (2+6)/4
f^(-1)(2) = 8/4 = 2
3) If f(x) = 6x and g(x) = x+6
f(g(x)) = f(x+6)
f(x+6) = 6(x+6)
Since x = 1
f(g(1)) = 6(1+6)
f(g(1)) = 6(7)
f(g(1)) = 42
<span>The answer is that 79 IS NOT correct because the riddle says "my ones digit is 2 LESS than my tens digit.." and 79 has 7 in tens and 9 in ones.</span>
Answer:
D. Population, because it is a collection of salaries for all teachers in the school.
Step-by-step explanation:
In research, population refers to a complete set of subjects that share a characteristic and that the researcher is interested in. On the other hand, a sample is a subset of a population and it's usually the one the researcher takes to make a study with.
In this example, we have "The salary of each teacher in a school" since we are taking ALL the teachers of this school, this would be a population. If we were working with the salary of only a portion of the teachers of said school, it would be a sample.
Thus, the right answer is D. Population, because it is a collection of salaries for all teachers in the school.
Given:
Scale of the map 1 1/4cm : 8 yards
Rectangular Park: width : 2 1/2 cm ; length : 6 1/4 cm
Circular Pond: pi = 3.14 ; diameter 1 1/4 cm
Convert mixed factions into fractions.
Scale 1 1/4 = (4*1+1)/4 = 5/4
Width: 2 1/2 = (2*2+1)/2 = 5/2
Length: 6 1/4 = (4*6+1)/4 = 25/4
Diameter: 1 1/4 = (4*1+1)/4 = 5/4
width / scale * 8 yds = width in yards
5/2 ÷ 5/4 = 5/2 * 4/5 = 20/10 = 2 * 8 yds = 16 yds
length / scale * 8 yds = length in yards
25/4 ÷ 5/4 = 25/4 * 4/5 = 100/20 = 5 * 8 yds = 40 yds
Area of a rectangular park = l * w = 40 yds * 16 yds = 640 yds²
diameter / scale * 8 yds = diameter in yards
5/4 ÷ 5/4 = 5/4 * 4/5 = 20/20 = 1 * 8 yds = 8 yds.
radius = d/2 = 8/2 = 4
Area of a circular pond = πr² = 3.14 * 4² = 3.14 * 16yds² = 50.24 yds²