19. What is the sum, if (3x2y +2xy - 2y?) is added to (5y2 - 7x²y + 2xy)?
A. 8x²y - 5xy - y2
B. 8x2y + 4xy - 9y2
C. -4x2y + 4xy + 3y2 D. 4x2 - 4xy - 3
20. What must be added to x-8 to obtain 0?
A. X-8
B.X + 8
C. -X + 8
D. -X-8
21. What is the difference when -3x - 2 is subtracted from 4x - 5?
A. 7x + 3
B. 7x - 3
C.-7x + 3
D. -7X-3
- 22. What is the value of the expression (7x)2 if x = 1?
A. 14
B. 49
C. 7
D. 71
23. What is the value of the expression
2x+3
when x = a and y = 3?
y-2
A. 5
B. 6
C. 7
D. 8
24. What is the value of the expression, (30m + 5) + n: m = 12 and n = 15?
A. 15
B. 25
C. 35
D. 45
25. What is the value of the expression x2 - y2 + z when x = 3, y = 2 and z = 5?
A. 5
B. 10
C. 15
D. 20
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