17. Which is the numerical coefficient in the expression 6xy3z5 ?
A. 3
B. 5
C.xyz
D. 6
18. An expression is a polynomial if
A. The variable is inside the radical sign. .
B. There is a variable in the denominator.
C. The exponent of the variable is negative.
D. Each term is constant, a variable or a product of a constant and variable.
19. What is the degree of the polynomial 3x2y3 – xy2 + 2x3y?
A. 5
B. 4
C. 3
D. 11
20. If x = 2 and y = 1, then x²y + y2 is equal to ?
A. 6
B. 7
C. 5
D.8
21. What is the difference if 10x2 - X - 3 is subtracted from 21x2 - 3x + 1?
A. 11x2 – 2x + 4 B. 11x2 + 2x - 4 C. 31x2 - 4x + 4 D. 11x2
22. What must be added to -18xy? to get 45xy2 ?
A. 27xy?
B. -27xy?
C. 63xy?
D. -63
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