1.
{(9/4, 7/8)}
Note that if you solved for only one of the two variables, you would earn only half credit. The solution of the system consists of an ordered pair (x, y) that satisfies both equations.
2.
A = x-intercept = 19/2
B = y-intercept = 19/3
[A fair amount of work is required. After you have an equation of the line, you can find A by setting y = 0 and can find B by setting x = 0.]
3.
center = (3, 2)
r = 7
[You have to complete the square and show your work.]
4.
(a) y > 2x/3 + 4
(b) The system x2 + y2 < 16 and y ³
x + 3
5.
In other words, one line is the line y = (Ö3)x/3 6, and
the other line is the line y = (Ö3)x/3 6.
[We did this in class. Please check your notes.]
6.
7.
(a) 24 cubic units
(b) 5 by inspection (3-4-5 rt. triangle)
(c) 18 + 6Ö41 square units
8.
(a) Almost everyone was able to do this.
(b) (1, 2)
(c) 5Ö2
(d) y 5 = 3(x 2), or some people simplified to get y = 3x + 11
(e) 2Ö10
Explanation: You have to find an equation for lines AC and BF (where F is the foot of the altitude), find their intersection (namely the point (4, 1)), and then use the distance formula. Or, you could use Heros Formula in part (f) and work backwards.
(f) 40 square units by formula A = ½ bh, where h was computed in part (e)