Answer: [tex]30[/tex]
Step-by-step explanation:
Given
[tex]k(x)=2x+3[/tex]
[tex]M(x)=3x^2+7x-10[/tex]
[tex]M\left(k(x)\right)[/tex] is given by replacing the [tex]x[/tex] by [tex]k(x)[/tex] from the [tex]M(x)[/tex]
[tex]\Rightarrow M\left(k(x)\right)=3(2x+3)^2+7(2x+3)-10\\\Rightarrow M\left(k(x)\right)=3(4x^2+9+12x)+14x+21-10\\\Rightarrow M\left(k(x)\right)=12x^2+50x+38[/tex]
Now, [tex]M\left(k(-4)\right)[/tex] is
[tex]\Rightarrow M\left(k(-4)\right)=12(-4)^2+50(-4)+38\\\Rightarrow M\left(k(-4)\right)=192-200+38\\\Rightarrow M\left(k(-4)\right)=30[/tex]