Respuesta :
Answer:
28
Step-by-step explanation:
So this means to replace the r you see in 4r^2-8 with 3.
Let's do that:
4(3)^2-8
Now to simplify this just use pemdas or a calculator:
4(9)-8 since 3^2 means 3*3=9
36-8
28
Answer:
28.
Step-by-step explanation:
Put r =- 3 and work it out:
That would be 4(3)^2 - 8
= 4 * 9 - 8
= 36 - 8
= 28.
