Answer:
2a^4c-2ac^2-15
Step-by-step explanation:
Sorry, I not sure if this is right or not cause I don't know if the exponent for -4a^4c is that or -4a^4c-15, but I'm just going to go with -4a^4c. However aside from that you just combine like terms.
View explanations and answer in the picture
Answer:
66 m²
Step-by-step explanation:
A = ½ (a + b) h
A = ½ (10 + 12) (6)
A = 66
The area is 66 m².
Answer:
390625
Step-by-step explanation:
The questions are all independent -- the answer on one question does not limit the number of possible answers on another question.
The quiz has 5 choices for each question, so there are
ways to answer the quiz questions.
Notice that this could be written
. You could say that the number of ways to answer the questions is

Use a calculator to find 
We can automatically see that we are dealing with a percent decrease because we are going from a smaller to a bigger number. We need to first find what percent of 140the number 84 is. to do this we can set up the following equation:
140/84=100/x (this equation is basically saying if 140 is 100(%) what would 84 be?)
solving for x here gives us x = (84 X 100)/140 = 60, so 84 is 60 percent of 140 which means 140 decreased by 40 percent.
Let me know if I can clear anything else up.