Answer:
or 
Step-by-step explanation:
we know that
Applying the law of cosines

In this problem we have



substitute the values



Answer:
Any line with the same slope. In this case the slope is 1. For example, y=x+4 is parallel to y=x+7.
The shortest distance from a point to a straight line is the
measurement of the line segment which connects the point to the straight line.
This line segment should be perpendicular to the line and is thus called the
perpendicular distance.
Step-by-step explanation:
The number of people to paint the bridge is inversely proportional to the number of hours it takes.
(If there are more people, it will take less time etc.)
9 people can paint the bridge in 5 hours.
=> 2 people can paint the bridge in 5 * (9/2) = 22.5 hours.
Answer:
4(3) - 7 = 4(3 - 1) - 3
12 - 7 = 4(2) - 3
5 = 8 - 3
= 5
They are equivalent because when they are both simplified they have the same answer 5