Will give brainlist soon as i can is this a rhombus? ?

No- a Parallelogram

Step-by-step explanation:

By inspection, that is without doing any calculations

A rectangle has 4 right angles at the vertices ← not the case here

A rhombus has 4 congruent sides ← not the case here

A parallelogram has opposite sides parallel and congruent ← Yes

A square has  4 congruent sides and right angles at vertices ← not the case

answer: cos [   arcsin (3/5) - arccos (1/2) ] =

step-by-step explanation: × = 3/5 = 0.6--> x = 36.87 and x = 180 - 36.87 = 143.13 deg

cos y = 1/2 --> y = +- 60 deg a. cos (x - y) = cos (143.13 - 60) = cos 83,13  

=

0.12

b. cos (36.87 - 60) = cos (-23.23) = 0.92