Evaluate the following expressions when x = -2, y = 6, and z = -4
y^2 + 3z
5y - 3(x^2 + 1) + z
#1.
6^2 + 3(-4)
#2.
5(6)-3((-2)^2+1)+(-4)
Class 6
To evaluate the given expressions, we substitute the given values of x, y, and z into the expressions and then simplify them. Let's start by evaluating the first expression:
Expression 1: y^2 + 3z
Substituting the values:
y^2 + 3z = 6^2 + 3(-4)
Simplifying:
y^2 + 3z = 36 + (-12) = 24
Therefore, when x = -2, y = 6, and z = -4, the value of the first expression y^2 + 3z is 24.
Now let's move on to evaluating the second expression:
Expression 2: 5y - 3(x^2 + 1) + z
Substituting the values:
5y - 3(x^2 + 1) + z = 5(6) - 3((-2)^2 + 1) + (-4)
Simplifying:
5y - 3(x^2 + 1) + z = 30 - 3(4 + 1) - 4
= 30 - 3(5) - 4
= 30 - 15 - 4
= 15 - 4
= 11
Therefore, when x = -2, y = 6, and z = -4, the value of the second expression 5y - 3(x^2 + 1) + z is 11.
In summary:
Expression 1: y^2 + 3z = 24
Expression 2: 5y - 3(x^2 + 1) + z = 11