Answer:
The rule which allows us to change the sign of an exponent is called the <u>negative exponent</u> rule.
Step-by-step explanation:
Consider the provided information.
The negative exponent rule is the rule which allows to change the sign of an exponent.

According to negative exponent rule: A negative exponents in the numerator moved to the denominator and become positive exponents.
If A negative exponents in the denominator moved to the numerator and become positive exponents.
Hence, the required statement is: The rule which allows us to change the sign of an exponent is called the <u>negative exponent</u> rule.
Answer:

Step-by-step explanation:
We are given with two equations
first equation is 
second equation is

we find the result of subtracting two equation
subtract the second equation from the first, so
first equation - second equation, multiply second equation by -1 and then add it with first equation


Now add both equations, we get

Answer:
V = 31.5 in ^3
Step-by-step explanation:
The volume is Bh
The base is the triangle
B = 1/2 (7) *2
B = 7 in^2
Now find the volume
V = 7* 4.5
V = 31.5 in ^3
Answer:
21=3(4)+9
Step-by-step explanation:
Assuming that the equation that you are trying the get is y=mx+b, plug in m, x, and b to get:
y=3(4)+9
y=12+9
y=21
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