Step-by-step explanation:
a) ( 2x+y) + 3y ( y-z) -2x ( x-y )
↪ (2× -1 + 1) + 3 × 1 (1 - 2) - 2 × -1 (-1 -1)
↪ -1 + 3 × -1 × - 2 × -1 × -2
↪ -1 + 12 = 11 , answer
b) ( x-2y) ( 3x² + 4xy - y²)
↪ (-1 - 2 × 1) (3 × -1² + 4 × -1 × 1 - 1²)
↪ -3 × (- 3 - 1 - 4 - 1)
↪ -3 × -9
↪ 27, answer
c) ( x³ + y³ - z³) ( 2x + y -z)
↪ (-1³ + 1³ - 2³) (2 × -1 + 1 × -2³)
↪ (-1 + 1 - 8) (-2 - 8)
↪ -8 × -10 = 80, answer
Answer:
The real numbers include all the rational numbers, such as the integer −5 and the fraction 4/3, and all the irrational numbers, such as 2 (1.41421356..., the square root of 2, an irrational algebraic number).
Answer: x=4
10x-3x=30-2
7x=28
X=4