Answer:
Mr.Lin's present age is 30 years now. His son is 8 years old now.
Step-by-step explanation:
Let L = Mr.Lin's present age,
S = his son's present age.
First equation is
L + S = 38. (1)
The second equation is
L + 3 = 3*(S+3) (2) ("In three years' time, Mr.Lin will be three times as old as his son.")
From (1), express S = 38-L and substitute it into (2). You will get
L + 3 = 3*((38-L)+3), or
L + 3 = 114 - 3L + 9,
4L = 114 + 9 - 3,
4L = 120,
L = 30.
ANSWER

EXPLANATION
The total number of students can be calculated by adding all the frequencies.
From the graph the total frequency is,

The number of students who intend to go into state or local government after graduation is 78.
The percentage of students who intend to go into state or local government after graduation


Answer:
x=2 : )
Step-by-step explanation:
4(3x-1)=20
12x-4=20
12x=24
x=2
Given:
In parallelogram ABCD, two of its vertices are A(-4,0) and B(0,3).
To find:
The equation that represents a line that contain CD.
Solution:
We have,
A(-4,0) and B(0,3)
Slope of AB is



The slope of line AB is
.
Opposite sides of a parallelogram are parallel and slopes of parallel lines are equal.
In parallelogram ABCD, AB and CD are opposite sides. So, their slopes must be equal.
Slope of line AB = Slope of line CD = 
The slope intercept form of a line is

Where, m is slope and b is y-intercept.
Slope of line CD is
, it means the line must be of the form

Coefficient of x is
only in option a.
Therefore, the correct option is a.