Answer:
x = 24.48, y = -15.52, z = 3.95 to the nearest hundredth.
Step-by-step explanation:
x+y-z=5 (a)
-x-4y-8z=6 (b)
3x+5y-4z=-20 (c)
Adding equations a and b:
-3y - 9z = 11 (d)
Now multiply equation b by 3:
-3x - 12y - 24z = 18 (e)
Adding c and e:
-7y - 28z = -2 (f) Multiply by 3 to give (g)
-3y - 9z = 11 (b) Multiply by -7 to give (h)
-21y - 84z = -6 (g)
21y + 63z = -77 (h) Adding g and h:
-21z = - 83
z = 3.952
and y is found bt substituting in equation d:
-3y - 9(3.952) = 11
y = ( 11 + 9(3.952) / -3
= -15.52.
Now find x by substituting for y an z in equation a:
x - 15.52 - 3.952 = 5
x = 5 + 15.52 + 3.952
= 24.476.
Answer:
y = 25 degrees
Step-by-step explanation:
We start with 115° and x -
115° + x = 180°
x = 180° - 115°
x = 65°
The sum of all of the angles of a triangle will <em>always</em> be 180 degrees -
x + y + 90° = 180°
We substitute x with 65° -
65° + y + 90° = 180°
y = 180° - 65° - 90°
y = 90° - 65°
y = 25°
Answer:
Step-by-step explanation:
From the information given,
Mark: 6,7,8,9,10
frequency:5,4,7,10,4
a) Range = highest mark - lowest mark
Range = 10 - 6 = 4
b) The number of students in the group is the sum of the frequency. Therefore,
Number of students = 5 + 4 + 7 + 10 + 4 = 30 students
c) Mean mark = (mark × frequency)/total frequency
[(6 × 5) + (7 × 4) + (8 × 7) + (9 × 10) + 10 × 4)]/ 30
Mean mark = (30 + 28 + 56 + 90 + 40)/30 = 244/30
Mean mark = 8.1
Answer:
Step-by-step explanation:
x=140°
m || n
