Let

, where

and let

be any real constant.
Given this definition of scalar multiplication, we can see right away that there is no identity element

such that

because
Answer:
the answer is D
Step-by-step explanation:
In the middle:
x-coordinate= {7-(-1)}/2= 4
y-coordinate= (8-2)/2= 3
So centre is (4,3)

please mark me as brainlist
Answer:
<em>Mechanic A worked for 5 hours</em> and <em>Mechanic B worked for 15 hours</em>
I hope my answer and explanation helped!
<u>okay to get started you need to make a system of equations:</u>
x= number of hours worked by mechanic A
y= number of hours worked by mechanic B
x + y= 20
95x + 60y= 1375
<u>substitute in an equation:</u>
x + y= 20
y= 20- x
95x + 60(20-x)=1375
<u>Solve for x</u>
95x + 1200 - 60x=1375
35x =175
x= 5
<u>plug in x to solve for y</u>
x + y= 20
5 + y= 20
y=15
<u>Check work</u>
then you're done :D