Answer:
Concept:
Here, we need to understand the idea of evaluation.
When encountering questions that gave you an expression with variables, then stated: "If x = a, y = b, z = c" (a, b, c are all constants), this means you should substitute the value given for each variable back to the expression.
Solve:
Given information
a = 5
b = 2
Given expression
-2ab
Substitute values into the expression
-2 (5) (2)
Simplify by multiplication
=-10 (2)
=[tex]\boxed{-20}[/tex]
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Given information
a = 5
b = 2
Given expression
-3a + b
Substitute values into the expression
-3 (5) + (2)
SImplify by multiplication
=-15 + (2)
Simplify by addition
=[tex]\boxed{-13}[/tex]
Hope this helps!! :)
Please let me know if you have any questions
