(Someone help) How would we know that a rectangle that is 3 1/2 inches by 2 1/4 inches has an area of 7 7/8 square inches?

use the area formula

Step-by-step explanation:

A=wl

multiply 3.5 times 2.25

hope it you

step-by-step explanation:

sin(7pi/6 - pi/3)  

= sin(7pi/6 - 2pi/6)  

= sin(5pi/6)  

= sin(pi - pi/6)  

= sin(pi/6)  

= 1/2  

sin 7pi/6 - sin pi/3  

= sin (pi + pi/6) - sin pi/3  

= -sin pi/6 - sin pi/3  

= -1/2 - sqrt(3)/2  

= -(1+sqrt(3))2