Answer:
Step-by-step explanation:
Declaration
Let Heather's number of messages = x
Let Eric's number of messages = x + 9
Let Chang's number of messages = 3(x +9)
Equation
x + x + 9 + 3(x + 9) = 116
Solution
x + x + 9 + 3(x + 9) = 116 Remove the brackets
x + x + 9 + 3x + 27 = 116 Combine like terms
x + x + 3x + 9 + 27 = 116
5x + 36 = 116 Subtract 36 from both sides
5x + 36 - 36 = 116 - 36 Combine
5x = 80 Divide both sides by 5
5x/5 = 80/5
x = 16
Answer
Heather = 16
Eric = 16 + 9 = 25
Chang = 3*25 = 75
Answer:
Option C is correct i.e. 2.
Step-by-step explanation:
Given the function is f(x) = x² +8x -2.
We can compare it with general quadratic expression i.e. ax² +bx +c.
Then a = 1, b = 8, c = -2.
We can find the number of real root by finding discriminant of the equation ax² +bx +c =0 as follows:-
D = b² -4ac
D = 8² -4*1*-2
D = 64 +8
D = 72.
When D is a positive value, then we have two real roots of the equation.
Hence, option C is correct i.e. 2.
Answer:
Step-by-step explanation:
The right statistical procedure is by applying a hypothesis test that uses a single mean. Here, if we are to talk about comparison, it should be between the mean IQ of the students in the class and the national average IQ. The class is not for a comparison between two population means because it is viewed as the sample of the population. That is to say, the required task is to determine if the sample mean is greater than the population mean. We can conclude that this obeys a hypothesis test rather than a confidence interval.
Answer:
4 inches deep, 5 inches high and 15 inches across
Answer:
2d +18
Step-by-step explanation:
use distributive property:
a(b+c)
= ab+ac