Write the augmented matrix for each system of equations.
- 2x - 2y + 5z - 1
-Sx - 5y + 72 - 4
9x - 2y + 2z = -1
a
c.
-2 -2
5
1
-2 -2
-5 -5
7
0
0
7:4
9 2
0
0
0:-
b.
d.
-2
-2 -25
-2 -5:-
-5 -5 7 : 4
5
7
9
2
-2 2-1
4

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

How to choose the sign of the radical in the denominator of the formula for the distance from a point to a line.

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?