Answer:
C. 
Step-by-step explanation:
Alan and his classmates found that the line of best fit through the data had the equation 
The slope of this line is 
If a line would intersect this line of best fit at right angles, then the two lines are perpendicular to each other.
The slopes of perpendicular lines are negative reciprocals of each other,
Hence that line must have slope 
Therefore we look for a line whose slope is
from the given options.
That line is the third option 
The answer is x= -3. 0.7(-3)-1.4=-3.5
Answer: Option (D) Add the exponents and keep the same base. Then find the reciprocal and change the sign of the exponent.
Explanation:
Given expression:

<em>Step-1: </em>Add the exponents and keep the same base by using
property.

Step-2: The reciprocal of
is
, which is 
Step-3: The exponent of
is +1; therefore, change the sign of exponent. The end expression will now become:

Hence, the correct option is (D) Add the exponents and keep the same base. Then find the reciprocal and change the sign of the exponent.
Answer:
I think the answer for x is 1
if the washer and dryer cost $790 then you would divide 790 by 2.
then you will get $395
then you add 40 to $395 and will get $435
so the answer is $435