there's 2 questions and one has 2 parts,,

1.)))Consider the algebraic expression -50+2a
a. write a sentence to describe the meaning of the algebraic expression
b. evaluate the expression when a=2.5

2.)))simplify the algebraic expression by using the distributive property first and then combining like terms
12z-18/6(*that's a fraction*)+4y

1. a. The algebraic expression -50+2a represents the sum of -50 and two times the value of a.

b. When a=2.5, we can substitute the value into the expression: -50 + 2(2.5). This simplifies to -50 + 5, resulting in -45.

2. Let's simplify the expression step by step:
First, we use the distributive property to distribute the terms outside the parentheses to the terms inside.
12z - (18/6) + 4y
Simplified: 12z - 3 + 4y

Next, we combine like terms, which are the terms that have the same variables and degrees.
The simplified expression becomes: 12z + 4y - 3.

1.) a. The algebraic expression -50+2a represents the sum of a negative constant (-50) and twice the value of variable "a."

b. To evaluate the expression when a=2.5, we substitute 2.5 for "a" in the expression:
-50 + 2(2.5)
= -50 + 5
= -45

2.) To simplify the algebraic expression 12z-18/6+4y using the distributive property and combining like terms:

First, simplify the fraction -18/6 by dividing the numerator (-18) by the denominator (6), which gives us:
-18/6 = -3

Next, distribute the coefficient 12 to both variables z and y:
12z + 4y

Finally, we combine like terms:
12z + 4y - 3

1. a) To describe the meaning of the algebraic expression -50+2a, we can say that it represents the result of subtracting 50 from twice the value of a.

b) To evaluate the expression when a = 2.5, we can substitute the value of a into the expression and perform the necessary calculations.

-50 + 2(2.5) = -50 + 5 = -45

Therefore, when a = 2.5, the value of the expression -50 + 2a is -45.

2. To simplify the algebraic expression 12z - 18/6 + 4y, we can start by using the distributive property and then combining like terms.

First, let's simplify the fraction -18/6 by dividing both the numerator and denominator by their greatest common divisor, which is 6:

-18/6 = -3

Now, we can rewrite the expression as:

12z -3 + 4y

Here, we have combined the simplified fraction -3 with the constant term -18/6.

Finally, we cannot simplify any further because all the terms are already unlike. So, the simplified expression is 12z - 3 + 4y.