Answer:
i. 33
ii. 1488
iii. 65
Step-by-step explanation:
i. 4x² − 3y² + 5z²
Putting the values x=2, y=-1 and z=2
4(2)² − 3(-1)² + 5(2)²
4×4 − 3×(1)² + 5×(4)
(16) - (3×1) + (20)
16 - 3+ 20
36 - 3
33
ii. 3x³ − 2x(4yz+5x²)
Putting the values x=2, y=-1 and z=2
[3(2)³ − 2×2(4×(-1)×2 + 5×(2)²)]
[3(8)³ − 2×2(-8 + 5×4)]
[3 ×512 - 2×2(-8 +20)]
[1536 - 4(12)]
[1536 - 48]
1488
iii. 1−4x(yz+3xy)
Putting the values x=2, y=-1 and z=2
[1 - 4 × 2((-1)×2 + 3×2×(-1))]
[1- 8(-2 + (-6))]
[1- 8 (-2 -6)]
[1 - 8(-8)]
[1 +64]
65
Independent
..............
Answer:
21C
22D
23B
24C
25A
Step-by-step explanation:
Answer:
(a) 7 essays and 29 multiple questions
(b) Your friend is incorrect
Step-by-step explanation:
Represent multiple choice with M and essay with E.
So:
--- Number of questions
--- Points
Solving (a): Number of question of each type.
Make E the subject of formula in 

Substitute 36 - M for E in 


Collect Like Terms


Divide both sides by -4


Substitute 29 for M in 


Solving (b): Can the multiple questions worth 4 points each?
It is not possible.
See explanation.
If multiple question worth 4 points each, then
would be:

Where x represents the number of points for essay questions.
Substitute 7 for E and 29 for M.


Subtract 116 from both sides



Make x the subject

Since the essay question can not have worth negative points.
Then, it is impossible to have the multiple questions worth 4 points
<em>Your friend is incorrect.</em>