Answer:
[tex]-2a^2-2a+11[/tex]
Step-by-step explanation:
To solve the question, use the given values of the variables and substitute them into the given expression.
We know that [tex]C = 2a^2-5[/tex] and [tex]D = 3-a[/tex]. With these values, we need to find [tex]2D-C[/tex]. So, substitute [tex]2a^2-5[/tex] for the [tex]C[/tex] and [tex]3-a[/tex] for the [tex]D[/tex] in that expression. Then, solve:
[tex]2D-C\\\\= 2(3-a)-(2a^2-5)\\= 6-2a-2a^2+5\\= -2a^2-2a+11[/tex]
Thus, [tex]2D-C[/tex] equals [tex]-2a^2-2a+11[/tex].