Answer: To evaluate 7a^4b^2 for a=-2 and b=-0.25, we can substitute these values into the expression and simplify:
7a^4b^2 = 7(-2)^4(-0.25)^2
First, we can simplify the powers of -2 and -0.25:
(-2)^4 = 16
(-0.25)^2 = 0.0625
Substituting these values into the expression, we get:
7a^4b^2 = 7(16)(0.0625)
Simplifying the multiplication, we get:
7a^4b^2 = 7(1)
Finally, we can simplify the expression to get the final answer:
7a^4b^2 = 7
Therefore, when a=-2 and b=-0.25, 7a^4b^2 is equal to 7.
Explanation: