Answer:
Explanation:
Let's break down the given expressions and substitute the given values to find the solutions.
1. 10y + 23x + 21:
To find the value of this expression, we need to substitute the given values for x and y. Since no specific values are given for x and y, we cannot determine the numerical value of the expression without further information. We can simplify it by combining like terms, but we cannot calculate a numerical answer.
2. x² + yz, if x = 4, y = -3, and z = 2:
Substituting the given values into the expression, we have:
x² + yz = 4² + (-3)(2) = 16 - 6 = 10
So, when x = 4, y = -3, and z = 2, the value of x² + yz is 10.
3. x + 3x + 2, if x = 15:
Substituting the given value of x into the expression, we have:
x + 3x + 2 = 15 + 3(15) + 2 = 15 + 45 + 2 = 62
So, when x = 15, the value of x + 3x + 2 is 62.